diff --git a/datafusion/physical-expr/src/expressions/not.rs b/datafusion/physical-expr/src/expressions/not.rs
index b63effdbb9c88..16061103ef589 100644
--- a/datafusion/physical-expr/src/expressions/not.rs
+++ b/datafusion/physical-expr/src/expressions/not.rs
@@ -25,7 +25,9 @@ use crate::PhysicalExpr;
 
 use arrow::datatypes::{DataType, FieldRef, Schema};
 use arrow::record_batch::RecordBatch;
-use datafusion_common::{Result, ScalarValue, cast::as_boolean_array, internal_err};
+use datafusion_common::{
+    Result, ScalarValue, cast::as_boolean_array, internal_datafusion_err, internal_err,
+};
 use datafusion_expr::ColumnarValue;
 use datafusion_expr::interval_arithmetic::Interval;
 #[expect(deprecated)]
@@ -181,6 +183,47 @@ impl PhysicalExpr for NotExpr {
         write!(f, "NOT ")?;
         self.arg.fmt_sql(f)
     }
+
+    #[cfg(feature = "proto")]
+    fn try_to_proto(
+        &self,
+        ctx: &datafusion_physical_expr_common::physical_expr::proto_encode::PhysicalExprEncodeCtx<'_>,
+    ) -> Result<Option<datafusion_proto_models::protobuf::PhysicalExprNode>> {
+        use datafusion_proto_models::protobuf;
+
+        Ok(Some(protobuf::PhysicalExprNode {
+            expr_id: None,
+            expr_type: Some(protobuf::physical_expr_node::ExprType::NotExpr(Box::new(
+                protobuf::PhysicalNot {
+                    expr: Some(Box::new(ctx.encode_child(&self.arg)?)),
+                },
+            ))),
+        }))
+    }
+}
+
+#[cfg(feature = "proto")]
+impl NotExpr {
+    /// Reconstruct a [`NotExpr`] from its protobuf representation.
+    pub fn try_from_proto(
+        node: &datafusion_proto_models::protobuf::PhysicalExprNode,
+        ctx: &datafusion_physical_expr_common::physical_expr::proto_decode::PhysicalExprDecodeCtx<'_>,
+    ) -> Result<Arc<dyn PhysicalExpr>> {
+        use datafusion_proto_models::protobuf;
+
+        let protobuf::PhysicalNot { expr } = match &node.expr_type {
+            Some(protobuf::physical_expr_node::ExprType::NotExpr(e)) => e.as_ref(),
+            _ => return internal_err!("PhysicalExprNode is not a NotExpr"),
+        };
+        let expr = expr.as_deref().ok_or_else(|| {
+            internal_datafusion_err!(
+                "NotExpr is missing required field 'expr' (expr_id: {:?}, expr_type: NotExpr)",
+                node.expr_id
+            )
+        })?;
+
+        Ok(Arc::new(NotExpr::new(ctx.decode(expr)?)))
+    }
 }
 
 /// Creates a unary expression NOT
@@ -198,6 +241,46 @@ mod tests {
     use arrow::{array::BooleanArray, datatypes::*};
     use datafusion_physical_expr_common::physical_expr::fmt_sql;
 
+    #[cfg(feature = "proto")]
+    #[test]
+    fn test_from_proto_missing_child() {
+        use datafusion_common::DataFusionError;
+        use datafusion_physical_expr_common::physical_expr::proto_decode::{
+            PhysicalExprDecode, PhysicalExprDecodeCtx,
+        };
+        use datafusion_proto_models::protobuf::{
+            PhysicalExprNode, PhysicalNot, physical_expr_node,
+        };
+
+        struct NoopDecoder;
+
+        impl PhysicalExprDecode for NoopDecoder {
+            fn decode(
+                &self,
+                _node: &PhysicalExprNode,
+                _schema: &Schema,
+            ) -> Result<Arc<dyn PhysicalExpr>> {
+                unreachable!("missing child should be rejected before decoding")
+            }
+        }
+
+        let node = PhysicalExprNode {
+            expr_id: Some(42),
+            expr_type: Some(physical_expr_node::ExprType::NotExpr(Box::new(
+                PhysicalNot { expr: None },
+            ))),
+        };
+        let schema = Schema::empty();
+        let decoder = NoopDecoder;
+        let ctx = PhysicalExprDecodeCtx::new(&schema, &decoder);
+
+        let err = NotExpr::try_from_proto(&node, &ctx).unwrap_err();
+        assert!(matches!(err, DataFusionError::Internal(msg)
+                if msg.contains("NotExpr is missing required field 'expr'")
+                    && msg.contains("expr_id: Some(42)")
+                    && msg.contains("expr_type: NotExpr")));
+    }
+
     #[test]
     fn neg_op() -> Result<()> {
         let schema = schema();
diff --git a/datafusion/proto/src/physical_plan/from_proto.rs b/datafusion/proto/src/physical_plan/from_proto.rs
index 96144b11e9d3a..cb2f20a23a816 100644
--- a/datafusion/proto/src/physical_plan/from_proto.rs
+++ b/datafusion/proto/src/physical_plan/from_proto.rs
@@ -312,13 +312,7 @@ pub fn parse_physical_expr_with_converter(
                 proto_converter,
             )?))
         }
-        ExprType::NotExpr(e) => Arc::new(NotExpr::new(parse_required_physical_expr(
-            e.expr.as_deref(),
-            ctx,
-            "expr",
-            input_schema,
-            proto_converter,
-        )?)),
+        ExprType::NotExpr(_) => NotExpr::try_from_proto(proto, &decode_ctx)?,
         ExprType::Negative(e) => {
             Arc::new(NegativeExpr::new(parse_required_physical_expr(
                 e.expr.as_deref(),
diff --git a/datafusion/proto/src/physical_plan/to_proto.rs b/datafusion/proto/src/physical_plan/to_proto.rs
index 5dd643c84ba21..6fc25fc0233c2 100644
--- a/datafusion/proto/src/physical_plan/to_proto.rs
+++ b/datafusion/proto/src/physical_plan/to_proto.rs
@@ -37,7 +37,7 @@ use datafusion_physical_expr::window::{SlidingAggregateWindowExpr, StandardWindo
 use datafusion_physical_expr_common::sort_expr::PhysicalSortExpr;
 use datafusion_physical_plan::expressions::{
     CaseExpr, CastExpr, DynamicFilterPhysicalExpr, IsNotNullExpr, IsNullExpr, Literal,
-    NegativeExpr, NotExpr, TryCastExpr, UnKnownColumn,
+    NegativeExpr, TryCastExpr, UnKnownColumn,
 };
 use datafusion_physical_plan::joins::{HashExpr, HashTableLookupExpr};
 use datafusion_physical_plan::udaf::AggregateFunctionExpr;
@@ -379,17 +379,6 @@ pub fn serialize_physical_expr_with_converter(
                 ),
             ),
         })
-    } else if let Some(expr) = expr.downcast_ref::<NotExpr>() {
-        Ok(protobuf::PhysicalExprNode {
-            expr_id,
-            expr_type: Some(protobuf::physical_expr_node::ExprType::NotExpr(Box::new(
-                protobuf::PhysicalNot {
-                    expr: Some(Box::new(
-                        proto_converter.physical_expr_to_proto(expr.arg(), codec)?,
-                    )),
-                },
-            ))),
-        })
     } else if let Some(expr) = expr.downcast_ref::<IsNullExpr>() {
         Ok(protobuf::PhysicalExprNode {
             expr_id,