diff --git a/addons/stock/models/stock_quant.py b/addons/stock/models/stock_quant.py
index 3cd70efc27e..e819385db73 100644
--- a/addons/stock/models/stock_quant.py
+++ b/addons/stock/models/stock_quant.py
@@ -459,6 +459,12 @@ class QuantPackage(models.Model):
             if move_lines_to_remove:
                 move_lines_to_remove.write({'result_package_id': False})
             else:
+                move_line_to_modify = self.env['stock.move.line'].search([
+                    ('package_id', '=', package.id),
+                    ('state', 'in', ('assigned', 'partially_available')),
+                    ('product_qty', '!=', 0),
+                ])
+                move_line_to_modify.write({'package_id': False})
                 package.mapped('quant_ids').write({'package_id': False})
 
     def action_view_picking(self):
diff --git a/addons/stock/tests/test_robustness.py b/addons/stock/tests/test_robustness.py
index 23442193a82..bd3dc6db96e 100644
--- a/addons/stock/tests/test_robustness.py
+++ b/addons/stock/tests/test_robustness.py
@@ -107,3 +107,41 @@ class TestRobustness(TransactionCase):
 
         # unreserve
         move1._do_unreserve()
+
+    def test_package_unpack(self):
+        """ Unpack a package that contains quants with a reservation
+        should also remove the package on the reserved move lines.
+        """
+        package = self.env['stock.quant.package'].create({
+            'name': 'Shell Helix HX7 10W30',
+        })
+
+        self.env['stock.quant']._update_available_quantity(
+            self.product1,
+            self.stock_location,
+            10,
+            package_id=package
+        )
+
+        # reserve a dozen
+        move1 = self.env['stock.move'].create({
+            'name': 'test_uom_rounding',
+            'location_id': self.stock_location.id,
+            'location_dest_id': self.customer_location.id,
+            'product_id': self.product1.id,
+            'product_uom': self.uom_unit.id,
+            'product_uom_qty': 10,
+        })
+        move1._action_confirm()
+        move1._action_assign()
+
+        move1.result_package_id = False
+
+        package.unpack()
+
+        # unreserve
+        move1._do_unreserve()
+        self.assertEqual(len(self.env['stock.quant']._gather(self.product1, self.stock_location)), 1)
+        self.assertEqual(len(self.env['stock.quant']._gather(self.product1, self.stock_location, package_id=package)), 0)
+
+        self.assertEqual(self.env['stock.quant']._gather(self.product1, self.stock_location).reserved_quantity, 0)