diff --git a/cmd/explaintest/r/tpch.result b/cmd/explaintest/r/tpch.result
index 34dc2a1920320..c27776be71af5 100644
--- a/cmd/explaintest/r/tpch.result
+++ b/cmd/explaintest/r/tpch.result
@@ -123,7 +123,11 @@ Sort_6	2.94	root	tpch.lineitem.l_returnflag:asc, tpch.lineitem.l_linestatus:asc
 └─Projection_8	2.94	root	tpch.lineitem.l_returnflag, tpch.lineitem.l_linestatus, 3_col_0, 3_col_1, 3_col_2, 3_col_3, 3_col_4, 3_col_5, 3_col_6, 3_col_7
   └─HashAgg_14	2.94	root	group by:col_13, col_14, funcs:sum(col_0), sum(col_1), sum(col_2), sum(col_3), avg(col_4, col_5), avg(col_6, col_7), avg(col_8, col_9), count(col_10), firstrow(col_11), firstrow(col_12)
     └─TableReader_15	2.94	root	data:HashAgg_9
+<<<<<<< HEAD
       └─HashAgg_9	2.94	cop	group by:tpch.lineitem.l_linestatus, tpch.lineitem.l_returnflag, funcs:sum(tpch.lineitem.l_quantity), sum(tpch.lineitem.l_extendedprice), sum(mul(tpch.lineitem.l_extendedprice, minus(1, tpch.lineitem.l_discount))), sum(mul(mul(tpch.lineitem.l_extendedprice, minus(1, tpch.lineitem.l_discount)), plus(1, tpch.lineitem.l_tax))), avg(tpch.lineitem.l_quantity), avg(tpch.lineitem.l_extendedprice), avg(tpch.lineitem.l_discount), count(1), firstrow(tpch.lineitem.l_returnflag), firstrow(tpch.lineitem.l_linestatus)
+=======
+      └─HashAgg_9	2.94	cop	group by:tpch.lineitem.l_linestatus, tpch.lineitem.l_returnflag, funcs:sum(tpch.lineitem.l_quantity), sum(tpch.lineitem.l_extendedprice), sum(mul(tpch.lineitem.l_extendedprice, minus(1, tpch.lineitem.l_discount))), sum(mul(mul(tpch.lineitem.l_extendedprice, minus(1, tpch.lineitem.l_discount)), plus(1, tpch.lineitem.l_tax))), count(tpch.lineitem.l_quantity), sum(tpch.lineitem.l_quantity), count(tpch.lineitem.l_extendedprice), sum(tpch.lineitem.l_extendedprice), count(tpch.lineitem.l_discount), sum(tpch.lineitem.l_discount), count(1)
+>>>>>>> b239f2f04... planner: split avg to count and sum for TableReader cop task (#11926)
         └─Selection_13	293795345.00	cop	le(tpch.lineitem.l_shipdate, 1998-08-15)
           └─TableScan_12	300005811.00	cop	table:lineitem, range:[-inf,+inf], keep order:false
 /*
@@ -982,7 +986,11 @@ Projection_16	1.00	root	div(11_col_0, 7.0)
       │   └─TableScan_31	300005811.00	cop	table:lineitem, range:[-inf,+inf], keep order:false
       └─HashAgg_40	9943040.00	root	group by:col_3, funcs:avg(col_0, col_1), firstrow(col_2)
         └─TableReader_41	9943040.00	root	data:HashAgg_36
+<<<<<<< HEAD
           └─HashAgg_36	9943040.00	cop	group by:tpch.lineitem.l_partkey, funcs:avg(tpch.lineitem.l_quantity), firstrow(tpch.lineitem.l_partkey)
+=======
+          └─HashAgg_36	9943040.00	cop	group by:tpch.lineitem.l_partkey, funcs:count(tpch.lineitem.l_quantity), sum(tpch.lineitem.l_quantity)
+>>>>>>> b239f2f04... planner: split avg to count and sum for TableReader cop task (#11926)
             └─TableScan_39	300005811.00	cop	table:lineitem, range:[-inf,+inf], keep order:false
 /*
 Q18 Large Volume Customer Query
diff --git a/planner/core/task.go b/planner/core/task.go
index 9a2258a7c3e9d..c9989459630ca 100644
--- a/planner/core/task.go
+++ b/planner/core/task.go
@@ -200,6 +200,34 @@ func (p *PhysicalMergeJoin) attach2Task(tasks ...task) task {
 	}
 }
 
+// splitCopAvg2CountAndSum splits the cop avg function to count and sum.
+// Now it's only used for TableReader.
+func splitCopAvg2CountAndSum(p PhysicalPlan) {
+	var baseAgg *basePhysicalAgg
+	if agg, ok := p.(*PhysicalStreamAgg); ok {
+		baseAgg = &agg.basePhysicalAgg
+	}
+	if agg, ok := p.(*PhysicalHashAgg); ok {
+		baseAgg = &agg.basePhysicalAgg
+	}
+	if baseAgg == nil {
+		return
+	}
+	for i := len(baseAgg.AggFuncs) - 1; i >= 0; i-- {
+		f := baseAgg.AggFuncs[i]
+		if f.Name == ast.AggFuncAvg {
+			sumAgg := *f
+			sumAgg.Name = ast.AggFuncSum
+			sumAgg.RetTp = baseAgg.Schema().Columns[i+1].RetType
+			cntAgg := *f
+			cntAgg.Name = ast.AggFuncCount
+			cntAgg.RetTp = baseAgg.Schema().Columns[i].RetType
+			cntAgg.RetTp.Flag = f.RetTp.Flag
+			baseAgg.AggFuncs = append(baseAgg.AggFuncs[:i], append([]*aggregation.AggFuncDesc{&cntAgg, &sumAgg}, baseAgg.AggFuncs[i+1:]...)...)
+		}
+	}
+}
+
 // finishCopTask means we close the coprocessor task and create a root task.
 func finishCopTask(ctx sessionctx.Context, task task) task {
 	t, ok := task.(*copTask)
@@ -232,6 +260,7 @@ func finishCopTask(ctx sessionctx.Context, task task) task {
 		p.stats = t.indexPlan.statsInfo()
 		newTask.p = p
 	} else {
+		splitCopAvg2CountAndSum(t.tablePlan)
 		p := PhysicalTableReader{tablePlan: t.tablePlan}.Init(ctx)
 		p.stats = t.tablePlan.statsInfo()
 		newTask.p = p