diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/NormalizeFloatingNumbers.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/NormalizeFloatingNumbers.scala
index 43738204c6704..8d5dbc7dc90eb 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/NormalizeFloatingNumbers.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/optimizer/NormalizeFloatingNumbers.scala
@@ -17,7 +17,7 @@
 
 package org.apache.spark.sql.catalyst.optimizer
 
-import org.apache.spark.sql.catalyst.expressions.{Alias, And, ArrayTransform, CreateArray, CreateMap, CreateNamedStruct, CreateStruct, EqualTo, ExpectsInputTypes, Expression, GetStructField, KnownFloatingPointNormalized, LambdaFunction, NamedLambdaVariable, UnaryExpression}
+import org.apache.spark.sql.catalyst.expressions.{Alias, And, ArrayTransform, CreateArray, CreateMap, CreateNamedStruct, CreateStruct, EqualTo, ExpectsInputTypes, Expression, GetStructField, If, IsNull, KnownFloatingPointNormalized, LambdaFunction, Literal, NamedLambdaVariable, UnaryExpression}
 import org.apache.spark.sql.catalyst.expressions.codegen.{CodegenContext, ExprCode}
 import org.apache.spark.sql.catalyst.planning.ExtractEquiJoinKeys
 import org.apache.spark.sql.catalyst.plans.logical.{LogicalPlan, Subquery, Window}
@@ -123,7 +123,8 @@ object NormalizeFloatingNumbers extends Rule[LogicalPlan] {
       val fields = expr.dataType.asInstanceOf[StructType].fields.indices.map { i =>
         normalize(GetStructField(expr, i))
       }
-      CreateStruct(fields)
+      val struct = CreateStruct(fields)
+      KnownFloatingPointNormalized(If(IsNull(expr), Literal(null, struct.dataType), struct))
 
     case _ if expr.dataType.isInstanceOf[ArrayType] =>
       val ArrayType(et, containsNull) = expr.dataType
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/DataFrameAggregateSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/DataFrameAggregateSuite.scala
index f7438f3ffec04..09f30bb5e2c77 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/DataFrameAggregateSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/DataFrameAggregateSuite.scala
@@ -1028,4 +1028,16 @@ class DataFrameAggregateSuite extends QueryTest
       checkAnswer(df, Row("abellina", 2) :: Row("mithunr", 1) :: Nil)
     }
   }
+
+  test("SPARK-32136: NormalizeFloatingNumbers should work on null struct") {
+    val df = Seq(
+      A(None),
+      A(Some(B(None))),
+      A(Some(B(Some(1.0))))).toDF
+    val groupBy = df.groupBy("b").agg(count("*"))
+    checkAnswer(groupBy, Row(null, 1) :: Row(Row(null), 1) :: Row(Row(1.0), 1) :: Nil)
+  }
 }
+
+case class B(c: Option[Double])
+case class A(b: Option[B])