diff --git a/tests/python/unittest/test_arith_intset.py b/tests/python/unittest/test_arith_intset.py
index 12214c596ce70..5b991151488e2 100644
--- a/tests/python/unittest/test_arith_intset.py
+++ b/tests/python/unittest/test_arith_intset.py
@@ -374,9 +374,9 @@ def test_union_lower_bound():
     assert result.min_value.same_as(neg_inf)
     assert result.max_value.same_as(pos_inf)
     set_2 = tvm.arith.IntervalSet(min_value=pos_inf, max_value=neg_inf)
-    result = tvm.arith.int_set.union_lower_bound([set_0, set_2])
+    result = tvm.arith.int_set.union_lower_bound([set_0, set_1, set_2])
     assert result.min_value.same_as(neg_inf)
-    assert result.max_value.same_as(0)
+    assert result.max_value.same_as(pos_inf)
 
 
 if __name__ == "__main__":