diff --git a/pydantic_ai_slim/pydantic_ai/messages.py b/pydantic_ai_slim/pydantic_ai/messages.py
index 88aa3fb1e9..1f3b5cd6e5 100644
--- a/pydantic_ai_slim/pydantic_ai/messages.py
+++ b/pydantic_ai_slim/pydantic_ai/messages.py
@@ -1070,7 +1070,7 @@ class FilePart:
 
     def has_content(self) -> bool:
         """Return `True` if the file content is non-empty."""
-        return bool(self.content)  # pragma: no cover
+        return bool(self.content.data)
 
     __repr__ = _utils.dataclasses_no_defaults_repr
 
diff --git a/tests/test_messages.py b/tests/test_messages.py
index d971ac46b3..627be2c928 100644
--- a/tests/test_messages.py
+++ b/tests/test_messages.py
@@ -422,6 +422,14 @@ def test_pre_usage_refactor_messages_deserializable():
     )
 
 
+def test_file_part_has_content():
+    filepart = FilePart(content=BinaryContent(data=b'', media_type='application/pdf'))
+    assert not filepart.has_content()
+
+    filepart.content.data = b'not empty'
+    assert filepart.has_content()
+
+
 def test_file_part_serialization_roundtrip():
     # Verify that a serialized BinaryImage doesn't come back as a BinaryContent.
     messages: list[ModelMessage] = [