diff --git a/extensions/tokenizers/rust/src/ndarray/reduce.rs b/extensions/tokenizers/rust/src/ndarray/reduce.rs
index 1c5739a44bb..d35bb97baa8 100644
--- a/extensions/tokenizers/rust/src/ndarray/reduce.rs
+++ b/extensions/tokenizers/rust/src/ndarray/reduce.rs
@@ -31,10 +31,17 @@ pub extern "system" fn Java_ai_djl_engine_rust_RustLibrary_sumWithAxis<'local>(
     keep_dims: jboolean,
 ) -> jlong {
     let tensor = cast_handle::<Tensor>(handle);
+    let rank = tensor.shape().rank() as i32;
     let axes = unsafe { env.get_array_elements(&axes, ReleaseMode::NoCopyBack) }.unwrap();
     let dims = axes
         .into_iter()
-        .map(|i| *i as usize)
+        .map(|i| {
+            let mut dim = *i as i32;
+            if dim < 0 {
+                dim = rank + dim;
+            }
+            return dim as usize;
+        })
         .collect::<Vec<usize>>();
 
     let ret = if keep_dims == JNI_TRUE {