diff --git a/cpp/velox/substrait/SubstraitToVeloxPlan.h b/cpp/velox/substrait/SubstraitToVeloxPlan.h
index 1485900af42fd..f8ad7d0727252 100644
--- a/cpp/velox/substrait/SubstraitToVeloxPlan.h
+++ b/cpp/velox/substrait/SubstraitToVeloxPlan.h
@@ -152,6 +152,12 @@ class SubstraitToVeloxPlanConverter {
   /// Get aggregation step from AggregateRel.
   core::AggregationNode::Step toAggregationStep(const ::substrait::AggregateRel& sAgg);
 
+  /// Helper Function to convert Substrait sortField to Velox sortingKeys and
+  /// sortingOrders.
+  std::pair<std::vector<core::FieldAccessTypedExprPtr>, std::vector<core::SortOrder>> processSortField(
+      const ::google::protobuf::RepeatedPtrField<::substrait::SortField>& sortField,
+      const RowTypePtr& inputType);
+
  private:
   /// Integrate Substrait emit feature. Here a given 'substrait::RelCommon'
   /// is passed and check if emit is defined for this relation. Basically a
@@ -328,12 +334,6 @@ class SubstraitToVeloxPlanConverter {
     std::vector<variant> values_;
   };
 
-  /// Helper Function to convert Substrait sortField to Velox sortingKeys and
-  /// sortingOrders.
-  std::pair<std::vector<core::FieldAccessTypedExprPtr>, std::vector<core::SortOrder>> processSortField(
-      const ::google::protobuf::RepeatedPtrField<::substrait::SortField>& sortField,
-      const RowTypePtr& inputType);
-
   /// Returns unique ID to use for plan node. Produces sequential numbers
   /// starting from zero.
   std::string nextPlanNodeId();
diff --git a/cpp/velox/substrait/SubstraitToVeloxPlanValidator.cc b/cpp/velox/substrait/SubstraitToVeloxPlanValidator.cc
index 2d4247f650c3e..352d23f667593 100644
--- a/cpp/velox/substrait/SubstraitToVeloxPlanValidator.cc
+++ b/cpp/velox/substrait/SubstraitToVeloxPlanValidator.cc
@@ -358,6 +358,34 @@ bool SubstraitToVeloxPlanValidator::validate(const ::substrait::FetchRel& fetchR
     logValidateMsg("native validation failed due to: Offset and count should be valid in FetchRel.");
     return false;
   }
+
+  core::PlanNodePtr childNode;
+  // Check the input of fetchRel, if it's sortRel, we need to check whether the sorting key is duplicated.
+  ::substrait::SortRel sortRel;
+  bool topNFlag;
+  if (fetchRel.has_input()) {
+    topNFlag = fetchRel.input().has_sort();
+    if (topNFlag) {
+      sortRel = fetchRel.input().sort();
+      childNode = planConverter_.toVeloxPlan(sortRel.input());
+    } else {
+      childNode = planConverter_.toVeloxPlan(fetchRel.input());
+    }
+  }
+
+  if (topNFlag) {
+    auto [sortingKeys, sortingOrders] = planConverter_.processSortField(sortRel.sorts(), childNode->outputType());
+
+    folly::F14FastSet<std::string> sortingKeyNames;
+    for (const auto& sortingKey : sortingKeys) {
+      auto result = sortingKeyNames.insert(sortingKey->name());
+      if (!result.second) {
+        logValidateMsg(
+            "native validation failed due to: if the input of fetchRel is a SortRel, we will convert it to a TopNNode. In Velox, it is important to ensure unique sorting keys. However, duplicate keys were found in this case.");
+        return false;
+      }
+    }
+  }
   return true;
 }