diff --git a/apps/inm/serializers.py b/apps/inm/serializers.py
index 13c6ccc1..6e6515a9 100644
--- a/apps/inm/serializers.py
+++ b/apps/inm/serializers.py
@@ -236,7 +236,7 @@ class MIODoSerializer(CustomModelSerializer):
         model = MIO
         fields = ['id', 'number', 'note', 'do_user',
                   'belong_dept', 'type', 'inout_date', 'mgroup', 'mio_user']
-        extra_kwargs = {'inout_date': {'required': True}, 'do_user': {'required': True}, 'number': {"required": False}}
+        extra_kwargs = {'inout_date': {'required': True}, 'do_user': {'required': True}, 'number': {"required": False, "allow_blank": True}}
 
     def validate(self, attrs):
         if 'mgroup' in attrs and attrs['mgroup']:
@@ -266,7 +266,7 @@ class MIOSaleSerializer(CustomModelSerializer):
     class Meta:
         model = MIO
         fields = ['id', 'number', 'note', 'order', 'inout_date', 'customer', 'mio_user']
-        extra_kwargs = {'inout_date': {'required': True}, 'number': {"required": False}}
+        extra_kwargs = {'inout_date': {'required': True}, 'number': {"required": False, "allow_blank": True}}
 
     def create(self, validated_data):
         validated_data['type'] = MIO.MIO_TYPE_SALE_OUT
@@ -293,7 +293,7 @@ class MIOPurSerializer(CustomModelSerializer):
     class Meta:
         model = MIO
         fields = ['id', 'number', 'note', 'pu_order', 'inout_date', 'supplier', 'mio_user']
-        extra_kwargs = {'inout_date': {'required': True}, 'number': {"required": False}}
+        extra_kwargs = {'inout_date': {'required': True}, 'number': {"required": False, "allow_blank": True}}
 
     def create(self, validated_data):
         validated_data['type'] = MIO.MIO_TYPE_PUR_IN
@@ -321,7 +321,7 @@ class MIOOtherSerializer(CustomModelSerializer):
         model = MIO
         fields = ['id', 'number', 'note', 'supplier',
                   'customer', 'type', 'inout_date', 'mio_user']
-        extra_kwargs = {'inout_date': {'required': True}, 'number': {"required": False}}
+        extra_kwargs = {'inout_date': {'required': True}, 'number': {"required": False, "allow_blank": True}}
 
     def create(self, validated_data):
         if not validated_data.get("number", None):
diff --git a/apps/pm/serializers.py b/apps/pm/serializers.py
index 9733d25f..37b895d4 100644
--- a/apps/pm/serializers.py
+++ b/apps/pm/serializers.py
@@ -25,7 +25,7 @@ class UtaskSerializer(CustomModelSerializer):
         model = Utask
         fields = '__all__'
         extra_kwargs = {
-            'number': {"required": False}
+            'number': {"required": False, "allow_blank": True}
         }
 
     def create(self, validated_data):