From 27c5bfd812512cbcd69122542a250a651e854019 Mon Sep 17 00:00:00 2001
From: Patrick Hoefler <61934744+phofl@users.noreply.github.com>
Date: Fri, 24 Feb 2023 18:54:47 +0000
Subject: [PATCH] Backport PR #51605: REGR: MultiIndex.isin with empty iterable
 raising

---
 pandas/core/indexes/multi.py            | 2 ++
 pandas/tests/indexes/multi/test_isin.py | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/pandas/core/indexes/multi.py b/pandas/core/indexes/multi.py
index 92cb7b5fd5f47..b381752818ba0 100644
--- a/pandas/core/indexes/multi.py
+++ b/pandas/core/indexes/multi.py
@@ -3748,6 +3748,8 @@ def delete(self, loc) -> MultiIndex:
     @doc(Index.isin)
     def isin(self, values, level=None) -> npt.NDArray[np.bool_]:
         if level is None:
+            if len(values) == 0:
+                return np.zeros((len(self),), dtype=np.bool_)
             if not isinstance(values, MultiIndex):
                 values = MultiIndex.from_tuples(values)
             return values.unique().get_indexer_for(self) != -1
diff --git a/pandas/tests/indexes/multi/test_isin.py b/pandas/tests/indexes/multi/test_isin.py
index bf003019d5387..2723e7e4db8eb 100644
--- a/pandas/tests/indexes/multi/test_isin.py
+++ b/pandas/tests/indexes/multi/test_isin.py
@@ -85,3 +85,11 @@ def test_isin_multi_index_with_missing_value(labels, expected, level):
     midx = MultiIndex.from_arrays([[np.nan, "a", "b"], ["c", "d", np.nan]])
     result = midx.isin(labels, level=level)
     tm.assert_numpy_array_equal(result, expected)
+
+
+def test_isin_empty():
+    # GH#51599
+    midx = MultiIndex.from_arrays([[1, 2], [3, 4]])
+    result = midx.isin([])
+    expected = np.array([False, False])
+    tm.assert_numpy_array_equal(result, expected)