diff --git a/py/torch_tensorrt/dynamo/lowering/_decompositions.py b/py/torch_tensorrt/dynamo/lowering/_decompositions.py
index f6226385de..37a7c42252 100644
--- a/py/torch_tensorrt/dynamo/lowering/_decompositions.py
+++ b/py/torch_tensorrt/dynamo/lowering/_decompositions.py
@@ -197,8 +197,13 @@ def slice_scatter_decomposition(
     dim_size = input_tensor.shape[dim]
     device_input_tensor = input_tensor.device
 
-    start = 0 if start is None else start  # Ensure start is int
-    start = get_positive_dim(start, input_tensor.shape[dim])
+    if start is None:
+        start = 0
+    elif isinstance(start, int):
+        start = get_positive_dim(start, dim_size)
+    elif isinstance(start, torch.SymInt):
+        if start < 0:
+            start = start + dim_size
     if end is None:  # Ensure end is int
         end = dim_size
     end = (