diff --git a/dart/test/keyword_test_keyword_test_generated.dart b/dart/test/keyword_test_keyword_test_generated.dart
index e0118af16..b9f764006 100644
--- a/dart/test/keyword_test_keyword_test_generated.dart
+++ b/dart/test/keyword_test_keyword_test_generated.dart
@@ -276,7 +276,7 @@ class Table2 {
 
   Table2T unpack() => Table2T(
       typeType: typeType,
-      type: type);
+      type: type?.unpack());
 
   static int pack(fb.Builder fbBuilder, Table2T? object) {
     if (object == null) return 0;
diff --git a/dart/test/monster_test_my_game.example_generated.dart b/dart/test/monster_test_my_game.example_generated.dart
index 7be3afa89..652b4509f 100644
--- a/dart/test/monster_test_my_game.example_generated.dart
+++ b/dart/test/monster_test_my_game.example_generated.dart
@@ -1337,7 +1337,7 @@ class Monster {
     ).vTableGetNullable(_bc, _bcOffset, 14),
     color: color,
     testType: testType,
-    test: test,
+    test: test?.unpack(),
     test4: test4?.map((e) => e.unpack()).toList(),
     testarrayofstring: const fb.ListReader<String>(
       fb.StringReader(),
@@ -1405,9 +1405,9 @@ class Monster {
       lazy: false,
     ).vTableGetNullable(_bc, _bcOffset, 88),
     anyUniqueType: anyUniqueType,
-    anyUnique: anyUnique,
+    anyUnique: anyUnique?.unpack(),
     anyAmbiguousType: anyAmbiguousType,
-    anyAmbiguous: anyAmbiguous,
+    anyAmbiguous: anyAmbiguous?.unpack(),
     vectorOfEnums: const fb.ListReader<Color>(
       Color.reader,
       lazy: false,
diff --git a/src/idl_gen_dart.cpp b/src/idl_gen_dart.cpp
index 52fc8772f..e2a060c97 100644
--- a/src/idl_gen_dart.cpp
+++ b/src/idl_gen_dart.cpp
@@ -606,7 +606,8 @@ class DartGenerator : public BaseGenerator {
       std::string defaultValue = getDefaultValue(field.value);
       bool isNullable = defaultValue.empty() && !struct_def.fixed;
       std::string nullableValueAccessOperator = isNullable ? "?" : "";
-      if (type.base_type == BASE_TYPE_STRUCT) {
+      if (type.base_type == BASE_TYPE_STRUCT ||
+          type.base_type == BASE_TYPE_UNION) {
         constructor_args +=
             field_name + nullableValueAccessOperator + ".unpack()";
       } else if (type.base_type == BASE_TYPE_VECTOR) {
diff --git a/tests/monster_test_my_game.example_generated.dart b/tests/monster_test_my_game.example_generated.dart
index 5554c4c4b..dc54f323f 100644
--- a/tests/monster_test_my_game.example_generated.dart
+++ b/tests/monster_test_my_game.example_generated.dart
@@ -1213,7 +1213,7 @@ class Monster {
       inventory: const fb.Uint8ListReader(lazy: false).vTableGetNullable(_bc, _bcOffset, 14),
       color: color,
       testType: testType,
-      test: test,
+      test: test?.unpack(),
       test4: test4?.map((e) => e.unpack()).toList(),
       testarrayofstring: const fb.ListReader<String>(fb.StringReader(), lazy: false).vTableGetNullable(_bc, _bcOffset, 24),
       testarrayoftables: testarrayoftables?.map((e) => e.unpack()).toList(),
@@ -1249,9 +1249,9 @@ class Monster {
       nonOwningReference: nonOwningReference,
       vectorOfNonOwningReferences: const fb.ListReader<int>(fb.Uint64Reader(), lazy: false).vTableGetNullable(_bc, _bcOffset, 88),
       anyUniqueType: anyUniqueType,
-      anyUnique: anyUnique,
+      anyUnique: anyUnique?.unpack(),
       anyAmbiguousType: anyAmbiguousType,
-      anyAmbiguous: anyAmbiguous,
+      anyAmbiguous: anyAmbiguous?.unpack(),
       vectorOfEnums: const fb.ListReader<Color>(Color.reader, lazy: false).vTableGetNullable(_bc, _bcOffset, 98),
       signedEnum: signedEnum,
       testrequirednestedflatbuffer: const fb.Uint8ListReader(lazy: false).vTableGetNullable(_bc, _bcOffset, 102),