diff --git a/sf_manufacturing/models/sale_order.py b/sf_manufacturing/models/sale_order.py
index e31faf1c..c22a26f5 100644
--- a/sf_manufacturing/models/sale_order.py
+++ b/sf_manufacturing/models/sale_order.py
@@ -166,4 +166,6 @@ class SaleOrderLine(models.Model):
             for line in self:
                 if vals['supply_method'] == 'automation' and line.manual_quotation:
                     raise UserError('当前（%s）产品为人工编程产品，不能选择自动化产线加工' % ','.join(line.mapped('product_id.name')))
+                if vals['supply_method'] == 'purchase' and line.is_incoming_material:
+                    raise UserError('当前（%s）产品为客供料，不能选择外购' % ','.join(line.mapped('product_id.name')))
         return super(SaleOrderLine, self).write(vals)