diff --git a/src/treebuilder.c b/src/treebuilder.c
index 1724f14..94036a8 100644
--- a/src/treebuilder.c
+++ b/src/treebuilder.c
@@ -108,6 +108,7 @@ TreeBuilder_get(TreeBuilder *self, PyObject *py_filename)
         return NULL;
 
     entry = git_treebuilder_get(self->bld, filename);
+    free(filename);
     if (entry == NULL)
         Py_RETURN_NONE;