diff --git a/onnxscript/function_libs/torch_lib/ops/core.py b/onnxscript/function_libs/torch_lib/ops/core.py
index 99c20eca18..48c64df4d4 100644
--- a/onnxscript/function_libs/torch_lib/ops/core.py
+++ b/onnxscript/function_libs/torch_lib/ops/core.py
@@ -3246,7 +3246,10 @@ def aten_div_mode(self: TReal, other: TReal, rounding_mode: Optional[str] = None
     if rounding_mode == "trunc":
         # Rounds the results of the division towards zero.
         # Equivalent to C-style integer division
-        return aten_trunc(op.Div(self, other))
+        quotient = op.Div(self, other)
+        if self.dtype == ir.DataType.FLOAT16:
+            quotient = op.Cast(quotient, to=FLOAT16.dtype)
+        return aten_trunc(quotient)
     if rounding_mode == "floor":
         return op.Floor(op.Div(self, other))
 
diff --git a/tests/function_libs/torch_lib/ops_test_data.py b/tests/function_libs/torch_lib/ops_test_data.py
index 3658a35b9d..e6c187fda2 100644
--- a/tests/function_libs/torch_lib/ops_test_data.py
+++ b/tests/function_libs/torch_lib/ops_test_data.py
@@ -676,16 +676,9 @@ def _where_input_wrangler(
     ),
     TorchLibOpInfo("true_divide", core_ops.aten_div),
     TorchLibOpInfo("true_divide", core_ops.aten_div_complex, complex=True),
-    TorchLibOpInfo("div_mode", core_ops.aten_div_mode)
-    .skip(
+    TorchLibOpInfo("div_mode", core_ops.aten_div_mode).skip(
         variant_name="no_rounding_mode",
         reason="this variation requires the rounding_mode argument",
-    )
-    .skip(
-        variant_name="trunc_rounding",
-        dtypes=(torch.float16,),
-        # Numbers match sometimes but not other times
-        reason="fixme: off-by-one. https://github.com/microsoft/onnxscript/issues/990",
     ),
     TorchLibOpInfo("dot", core_ops.aten_dot),
     TorchLibOpInfo(