diff --git a/Lib/test/test_zipapp.py b/Lib/test/test_zipapp.py
index 8fb0a68deba535c..9d354bb52ce6a06 100644
--- a/Lib/test/test_zipapp.py
+++ b/Lib/test/test_zipapp.py
@@ -279,6 +279,12 @@ def test_read_missing_shebang(self):
         zipapp.create_archive(str(source), str(target))
         self.assertEqual(zipapp.get_interpreter(str(target)), None)
 
+    def test_read_invalid_shebang(self):
+        # Test that an undecodable shebang is treated as having no interpreter.
+        target = self.tmpdir / 'source.pyz'
+        target.write_bytes(b'#!\xff\xfe\xff\xfe\nx')
+        self.assertIsNone(zipapp.get_interpreter(str(target)))
+
     def test_modify_shebang(self):
         # Test that we can change the shebang of a file.
         source = self.tmpdir / 'source'
diff --git a/Lib/zipapp.py b/Lib/zipapp.py
index a1cef18ada9d05d..7399c50a8b22cf7 100644
--- a/Lib/zipapp.py
+++ b/Lib/zipapp.py
@@ -175,7 +175,10 @@ def create_archive(source, target=None, interpreter=None, main=None,
 def get_interpreter(archive):
     with _maybe_open(archive, 'rb') as f:
         if f.read(2) == b'#!':
-            return f.readline().strip().decode(shebang_encoding)
+            try:
+                return f.readline().strip().decode(shebang_encoding)
+            except UnicodeDecodeError:
+                return None
 
 
 def main(args=None):
diff --git a/Misc/NEWS.d/next/Library/2026-10-01-05-01-08.gh-issue-158546.RtKp9M.rst b/Misc/NEWS.d/next/Library/2026-10-01-05-01-08.gh-issue-158546.RtKp9M.rst
new file mode 100644
index 000000000000000..5cfce8733eb70be
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-10-01-05-01-08.gh-issue-158546.RtKp9M.rst
@@ -0,0 +1 @@
+Treat an undecodable zipapp shebang as having no interpreter.