diff --git a/spark/src/main/scala/org/apache/comet/CometSparkSessionExtensions.scala b/spark/src/main/scala/org/apache/comet/CometSparkSessionExtensions.scala
index d52f31f54a..4449c9aad4 100644
--- a/spark/src/main/scala/org/apache/comet/CometSparkSessionExtensions.scala
+++ b/spark/src/main/scala/org/apache/comet/CometSparkSessionExtensions.scala
@@ -35,7 +35,7 @@ import org.apache.spark.sql.comet.execution.shuffle.{CometColumnarShuffle, Comet
 import org.apache.spark.sql.comet.util.Utils
 import org.apache.spark.sql.execution._
 import org.apache.spark.sql.execution.adaptive.{AQEShuffleReadExec, BroadcastQueryStageExec, ShuffleQueryStageExec}
-import org.apache.spark.sql.execution.aggregate.{BaseAggregateExec, HashAggregateExec, ObjectHashAggregateExec}
+import org.apache.spark.sql.execution.aggregate.{BaseAggregateExec, HashAggregateExec}
 import org.apache.spark.sql.execution.datasources._
 import org.apache.spark.sql.execution.datasources.csv.CSVFileFormat
 import org.apache.spark.sql.execution.datasources.json.JsonFileFormat
@@ -438,8 +438,7 @@ class CometSparkSessionExtensions
           }
 
         case op: BaseAggregateExec
-            if op.isInstanceOf[HashAggregateExec] ||
-              op.isInstanceOf[ObjectHashAggregateExec] =>
+            if op.isInstanceOf[HashAggregateExec] =>
           val groupingExprs = op.groupingExpressions
           val aggExprs = op.aggregateExpressions
           val resultExpressions = op.resultExpressions
diff --git a/spark/src/main/scala/org/apache/comet/serde/QueryPlanSerde.scala b/spark/src/main/scala/org/apache/comet/serde/QueryPlanSerde.scala
index 51b32b7dfc..bb7a3adf64 100644
--- a/spark/src/main/scala/org/apache/comet/serde/QueryPlanSerde.scala
+++ b/spark/src/main/scala/org/apache/comet/serde/QueryPlanSerde.scala
@@ -2813,8 +2813,7 @@ object QueryPlanSerde extends Logging with ShimQueryPlanSerde with CometExprShim
         }
 
       case aggregate: BaseAggregateExec
-          if (aggregate.isInstanceOf[HashAggregateExec] ||
-            aggregate.isInstanceOf[ObjectHashAggregateExec]) &&
+          if aggregate.isInstanceOf[HashAggregateExec] &&
             CometConf.COMET_EXEC_AGGREGATE_ENABLED.get(conf) =>
         val groupingExpressions = aggregate.groupingExpressions
         val aggregateExpressions = aggregate.aggregateExpressions