diff --git a/src/parser/converts/block.ts b/src/parser/converts/block.ts
index a25b2686..59f8c274 100644
--- a/src/parser/converts/block.ts
+++ b/src/parser/converts/block.ts
@@ -13,6 +13,30 @@ import type { Context } from "../../context"
 import { convertChildren } from "./element"
 import { getWithLoc, indexOf, lastIndexOf } from "./common"
 
+/** Get start index of block */
+function startBlockIndex(code: string, endIndex: number): number {
+    return lastIndexOf(
+        code,
+        (c, index) => {
+            if (c !== "{") {
+                return false
+            }
+            for (let next = index + 1; next < code.length; next++) {
+                const nextC = code[next]
+                if (!nextC.trim()) {
+                    continue
+                }
+                return (
+                    code.startsWith("#if", next) ||
+                    code.startsWith(":else", next)
+                )
+            }
+            return false
+        },
+        endIndex,
+    )
+}
+
 /** Convert for IfBlock */
 export function convertIfBlock(
     node: SvAST.IfBlock,
@@ -22,7 +46,7 @@ export function convertIfBlock(
     // {#if expr} {:else} {/if}
     // {:else if expr} {/if}
     const nodeStart = node.elseif
-        ? ctx.code.lastIndexOf("{", node.start)
+        ? startBlockIndex(ctx.code, node.start - 1)
         : node.start
     const ifBlock: SvelteIfBlock = {
         type: "SvelteIfBlock",
@@ -49,7 +73,7 @@ export function convertIfBlock(
         return ifBlock
     }
 
-    const elseStart = ctx.code.lastIndexOf("{", node.else.start)
+    const elseStart = startBlockIndex(ctx.code, node.else.start - 1)
 
     const elseBlock: SvelteElseBlock = {
         type: "SvelteElseBlock",
@@ -149,7 +173,7 @@ export function convertEachBlock(
         return eachBlock
     }
 
-    const elseStart = ctx.code.lastIndexOf("{", node.else.start)
+    const elseStart = startBlockIndex(ctx.code, node.else.start - 1)
 
     const elseBlock: SvelteElseBlock = {
         type: "SvelteElseBlock",
diff --git a/src/parser/converts/common.ts b/src/parser/converts/common.ts
index 12980efb..57370bb7 100644
--- a/src/parser/converts/common.ts
+++ b/src/parser/converts/common.ts
@@ -17,12 +17,12 @@ export function indexOf(
 /** lastIndexOf */
 export function lastIndexOf(
     str: string,
-    search: (c: string) => boolean,
+    search: (c: string, index: number) => boolean,
     end: number,
 ): number {
     for (let index = end; index >= 0; index--) {
         const c = str[index]
-        if (search(c)) {
+        if (search(c, index)) {
             return index
         }
     }
diff --git a/tests/fixtures/parser/ast/if-block01-input.svelte b/tests/fixtures/parser/ast/if-block01-input.svelte
new file mode 100644
index 00000000..0c10721d
--- /dev/null
+++ b/tests/fixtures/parser/ast/if-block01-input.svelte
@@ -0,0 +1 @@
+{#if expression}{:else if expression}{:else}{/if}
diff --git a/tests/fixtures/parser/ast/if-block01-no-undef-result.json b/tests/fixtures/parser/ast/if-block01-no-undef-result.json
new file mode 100644
index 00000000..0cc7e078
--- /dev/null
+++ b/tests/fixtures/parser/ast/if-block01-no-undef-result.json
@@ -0,0 +1,14 @@
+[
+  {
+    "ruleId": "no-undef",
+    "code": "expression",
+    "line": 1,
+    "column": 6
+  },
+  {
+    "ruleId": "no-undef",
+    "code": "expression",
+    "line": 1,
+    "column": 27
+  }
+]
\ No newline at end of file
diff --git a/tests/fixtures/parser/ast/if-block01-output.json b/tests/fixtures/parser/ast/if-block01-output.json
new file mode 100644
index 00000000..359c6b8e
--- /dev/null
+++ b/tests/fixtures/parser/ast/if-block01-output.json
@@ -0,0 +1,404 @@
+{
+  "type": "Program",
+  "body": [
+    {
+      "type": "SvelteIfBlock",
+      "elseif": false,
+      "expression": {
+        "type": "Identifier",
+        "name": "expression",
+        "range": [
+          5,
+          15
+        ],
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 5
+          },
+          "end": {
+            "line": 1,
+            "column": 15
+          }
+        }
+      },
+      "children": [],
+      "else": {
+        "type": "SvelteElseBlock",
+        "children": [
+          {
+            "type": "SvelteIfBlock",
+            "elseif": true,
+            "expression": {
+              "type": "Identifier",
+              "name": "expression",
+              "range": [
+                26,
+                36
+              ],
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 26
+                },
+                "end": {
+                  "line": 1,
+                  "column": 36
+                }
+              }
+            },
+            "children": [],
+            "else": {
+              "type": "SvelteElseBlock",
+              "children": [],
+              "range": [
+                37,
+                44
+              ],
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 37
+                },
+                "end": {
+                  "line": 1,
+                  "column": 44
+                }
+              }
+            },
+            "range": [
+              16,
+              49
+            ],
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 16
+              },
+              "end": {
+                "line": 1,
+                "column": 49
+              }
+            }
+          }
+        ],
+        "range": [
+          16,
+          49
+        ],
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 16
+          },
+          "end": {
+            "line": 1,
+            "column": 49
+          }
+        }
+      },
+      "range": [
+        0,
+        49
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 0
+        },
+        "end": {
+          "line": 1,
+          "column": 49
+        }
+      }
+    }
+  ],
+  "sourceType": "module",
+  "comments": [],
+  "tokens": [
+    {
+      "type": "Punctuator",
+      "value": "{",
+      "range": [
+        0,
+        1
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 0
+        },
+        "end": {
+          "line": 1,
+          "column": 1
+        }
+      }
+    },
+    {
+      "type": "MustacheKeyword",
+      "value": "#if",
+      "range": [
+        1,
+        4
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 1
+        },
+        "end": {
+          "line": 1,
+          "column": 4
+        }
+      }
+    },
+    {
+      "type": "Identifier",
+      "value": "expression",
+      "range": [
+        5,
+        15
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 5
+        },
+        "end": {
+          "line": 1,
+          "column": 15
+        }
+      }
+    },
+    {
+      "type": "Punctuator",
+      "value": "}",
+      "range": [
+        15,
+        16
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 15
+        },
+        "end": {
+          "line": 1,
+          "column": 16
+        }
+      }
+    },
+    {
+      "type": "Punctuator",
+      "value": "{",
+      "range": [
+        16,
+        17
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 16
+        },
+        "end": {
+          "line": 1,
+          "column": 17
+        }
+      }
+    },
+    {
+      "type": "MustacheKeyword",
+      "value": ":else",
+      "range": [
+        17,
+        22
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 17
+        },
+        "end": {
+          "line": 1,
+          "column": 22
+        }
+      }
+    },
+    {
+      "type": "MustacheKeyword",
+      "value": "if",
+      "range": [
+        23,
+        25
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 23
+        },
+        "end": {
+          "line": 1,
+          "column": 25
+        }
+      }
+    },
+    {
+      "type": "Identifier",
+      "value": "expression",
+      "range": [
+        26,
+        36
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 26
+        },
+        "end": {
+          "line": 1,
+          "column": 36
+        }
+      }
+    },
+    {
+      "type": "Punctuator",
+      "value": "}",
+      "range": [
+        36,
+        37
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 36
+        },
+        "end": {
+          "line": 1,
+          "column": 37
+        }
+      }
+    },
+    {
+      "type": "Punctuator",
+      "value": "{",
+      "range": [
+        37,
+        38
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 37
+        },
+        "end": {
+          "line": 1,
+          "column": 38
+        }
+      }
+    },
+    {
+      "type": "MustacheKeyword",
+      "value": ":else",
+      "range": [
+        38,
+        43
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 38
+        },
+        "end": {
+          "line": 1,
+          "column": 43
+        }
+      }
+    },
+    {
+      "type": "Punctuator",
+      "value": "}",
+      "range": [
+        43,
+        44
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 43
+        },
+        "end": {
+          "line": 1,
+          "column": 44
+        }
+      }
+    },
+    {
+      "type": "Punctuator",
+      "value": "{",
+      "range": [
+        44,
+        45
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 44
+        },
+        "end": {
+          "line": 1,
+          "column": 45
+        }
+      }
+    },
+    {
+      "type": "MustacheKeyword",
+      "value": "/if",
+      "range": [
+        45,
+        48
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 45
+        },
+        "end": {
+          "line": 1,
+          "column": 48
+        }
+      }
+    },
+    {
+      "type": "Punctuator",
+      "value": "}",
+      "range": [
+        48,
+        49
+      ],
+      "loc": {
+        "start": {
+          "line": 1,
+          "column": 48
+        },
+        "end": {
+          "line": 1,
+          "column": 49
+        }
+      }
+    }
+  ],
+  "range": [
+    0,
+    50
+  ],
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 2,
+      "column": 0
+    }
+  }
+}
\ No newline at end of file
diff --git a/tests/fixtures/parser/ast/if-block01-scope-output.json b/tests/fixtures/parser/ast/if-block01-scope-output.json
new file mode 100644
index 00000000..dc781fe1
--- /dev/null
+++ b/tests/fixtures/parser/ast/if-block01-scope-output.json
@@ -0,0 +1,197 @@
+{
+  "type": "global",
+  "variables": [
+    {
+      "name": "$$slots",
+      "identifiers": [],
+      "defs": [],
+      "references": []
+    },
+    {
+      "name": "$$props",
+      "identifiers": [],
+      "defs": [],
+      "references": []
+    },
+    {
+      "name": "$$restProps",
+      "identifiers": [],
+      "defs": [],
+      "references": []
+    }
+  ],
+  "references": [],
+  "childScopes": [
+    {
+      "type": "module",
+      "variables": [],
+      "references": [
+        {
+          "identifier": {
+            "type": "Identifier",
+            "name": "expression",
+            "range": [
+              5,
+              15
+            ],
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 5
+              },
+              "end": {
+                "line": 1,
+                "column": 15
+              }
+            }
+          },
+          "from": "module",
+          "init": null,
+          "resolved": null
+        },
+        {
+          "identifier": {
+            "type": "Identifier",
+            "name": "expression",
+            "range": [
+              26,
+              36
+            ],
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 26
+              },
+              "end": {
+                "line": 1,
+                "column": 36
+              }
+            }
+          },
+          "from": "module",
+          "init": null,
+          "resolved": null
+        }
+      ],
+      "childScopes": [
+        {
+          "type": "block",
+          "variables": [],
+          "references": [],
+          "childScopes": [],
+          "through": []
+        },
+        {
+          "type": "block",
+          "variables": [],
+          "references": [],
+          "childScopes": [],
+          "through": []
+        },
+        {
+          "type": "block",
+          "variables": [],
+          "references": [],
+          "childScopes": [],
+          "through": []
+        }
+      ],
+      "through": [
+        {
+          "identifier": {
+            "type": "Identifier",
+            "name": "expression",
+            "range": [
+              5,
+              15
+            ],
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 5
+              },
+              "end": {
+                "line": 1,
+                "column": 15
+              }
+            }
+          },
+          "from": "module",
+          "init": null,
+          "resolved": null
+        },
+        {
+          "identifier": {
+            "type": "Identifier",
+            "name": "expression",
+            "range": [
+              26,
+              36
+            ],
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 26
+              },
+              "end": {
+                "line": 1,
+                "column": 36
+              }
+            }
+          },
+          "from": "module",
+          "init": null,
+          "resolved": null
+        }
+      ]
+    }
+  ],
+  "through": [
+    {
+      "identifier": {
+        "type": "Identifier",
+        "name": "expression",
+        "range": [
+          5,
+          15
+        ],
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 5
+          },
+          "end": {
+            "line": 1,
+            "column": 15
+          }
+        }
+      },
+      "from": "module",
+      "init": null,
+      "resolved": null
+    },
+    {
+      "identifier": {
+        "type": "Identifier",
+        "name": "expression",
+        "range": [
+          26,
+          36
+        ],
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 26
+          },
+          "end": {
+            "line": 1,
+            "column": 36
+          }
+        }
+      },
+      "from": "module",
+      "init": null,
+      "resolved": null
+    }
+  ]
+}
\ No newline at end of file