diff --git a/.changeset/proud-pugs-clean.md b/.changeset/proud-pugs-clean.md
new file mode 100644
index 000000000..4d27faecb
--- /dev/null
+++ b/.changeset/proud-pugs-clean.md
@@ -0,0 +1,5 @@
+---
+"openapi-typescript": patch
+---
+
+fix: keyedParameters use unique key
diff --git a/packages/openapi-typescript/src/transform/path-item-object.ts b/packages/openapi-typescript/src/transform/path-item-object.ts
index 04aca3cd3..c57129893 100644
--- a/packages/openapi-typescript/src/transform/path-item-object.ts
+++ b/packages/openapi-typescript/src/transform/path-item-object.ts
@@ -53,7 +53,11 @@ export default function transformPathItemObject(pathItem: PathItemObject, option
     if (!("$ref" in operationObject)) {
       // important: OperationObject parameters come last, and will override any conflicts with PathItem parameters
       for (const parameter of [...(pathItem.parameters ?? []), ...(operationObject.parameters ?? [])]) {
-        const name = "$ref" in parameter ? options.ctx.resolve<ParameterObject>(parameter.$ref)?.name : parameter.name;
+        // fix: #1798, use unique key
+        const name =
+          "$ref" in parameter
+            ? `${options.ctx.resolve<ParameterObject>(parameter.$ref)?.in}-${options.ctx.resolve<ParameterObject>(parameter.$ref)?.name}`
+            : `${parameter.in}-${parameter.name}`;
         if (name) {
           keyedParameters[name] = parameter;
         }
diff --git a/packages/openapi-typescript/test/transform/path-item-object.test.ts b/packages/openapi-typescript/test/transform/path-item-object.test.ts
index ed0e697e3..1b3efea95 100644
--- a/packages/openapi-typescript/test/transform/path-item-object.test.ts
+++ b/packages/openapi-typescript/test/transform/path-item-object.test.ts
@@ -359,6 +359,66 @@ describe("transformPathItemObject", () => {
         },
       },
     ],
+    [
+      "parameters > header and cookie have same name param1",
+      {
+        given: {
+          get: {
+            parameters: [
+              {
+                name: "param1",
+                in: "header",
+                required: true,
+                schema: {
+                  type: "string",
+                },
+                description: "param1",
+              },
+              {
+                name: "param1",
+                in: "cookie",
+                required: true,
+                schema: {
+                  type: "string",
+                },
+                description: "param1",
+              },
+            ],
+          },
+        },
+        want: `{
+    parameters: {
+        query?: never;
+        header?: never;
+        path?: never;
+        cookie?: never;
+    };
+    get: {
+        parameters: {
+            query?: never;
+            header: {
+                /** @description param1 */
+                param1: string;
+            };
+            path?: never;
+            cookie: {
+                /** @description param1 */
+                param1: string;
+            };
+        };
+        requestBody?: never;
+        responses: never;
+    };
+    put?: never;
+    post?: never;
+    delete?: never;
+    options?: never;
+    head?: never;
+    patch?: never;
+    trace?: never;
+}`,
+      },
+    ],
   ];
 
   for (const [testName, { given, want, options = DEFAULT_OPTIONS, ci }] of tests) {