diff --git a/addons/mrp/models/mrp_production.py b/addons/mrp/models/mrp_production.py
index df6f3272b8d..70250d72e63 100644
--- a/addons/mrp/models/mrp_production.py
+++ b/addons/mrp/models/mrp_production.py
@@ -1143,3 +1143,15 @@ class MrpProduction(models.Model):
             return self.env.ref('mrp.exception_on_mo').render(values=values)
 
         self.env['stock.picking']._log_activity(_render_note_exception_quantity_mo, documents)
+
+    def button_unbuild(self):
+        self.ensure_one()
+        return {
+            'name': _('Unbuild'),
+            'view_mode': 'form',
+            'res_model': 'mrp.unbuild',
+            'view_id': self.env.ref('mrp.mrp_unbuild_form_view').id,
+            'type': 'ir.actions.act_window',
+            'context': {'default_mo_id': self.id, 'create': False, 'edit': False},
+            'target': 'new',
+        }
diff --git a/addons/mrp/models/mrp_unbuild.py b/addons/mrp/models/mrp_unbuild.py
index dbeeeb84fe7..9d57f1b71b9 100644
--- a/addons/mrp/models/mrp_unbuild.py
+++ b/addons/mrp/models/mrp_unbuild.py
@@ -106,8 +106,12 @@ class MrpUnbuild(models.Model):
     def _onchange_mo_id(self):
         if self.mo_id:
             self.product_id = self.mo_id.product_id.id
-            self.product_qty = self.mo_id.product_qty
+            self.bom_id = self.mo_id.bom_id
             self.product_uom_id = self.mo_id.product_uom_id
+            if self.has_tracking == 'serial':
+                self.product_qty = 1
+            else:
+                self.product_qty = self.mo_id.product_qty
 
     @api.onchange('product_id')
     def _onchange_product_id(self):
diff --git a/addons/mrp/tests/test_unbuild.py b/addons/mrp/tests/test_unbuild.py
index bf5c6e25f47..79aabcd0978 100644
--- a/addons/mrp/tests/test_unbuild.py
+++ b/addons/mrp/tests/test_unbuild.py
@@ -50,7 +50,6 @@ class TestUnbuild(TestMrpCommon):
         x.product_id = p_final
         x.bom_id = bom
         x.product_qty = 3
-        x.product_uom_id = self.uom_unit
         x.save().action_unbuild()
 
 
@@ -62,7 +61,6 @@ class TestUnbuild(TestMrpCommon):
         x.product_id = p_final
         x.bom_id = bom
         x.product_qty = 2
-        x.product_uom_id = self.uom_unit
         x.save().action_unbuild()
 
         self.assertEqual(self.env['stock.quant']._get_available_quantity(p_final, self.stock_location), 0, 'You should have 0 finalproduct in stock')
@@ -73,7 +71,6 @@ class TestUnbuild(TestMrpCommon):
         x.product_id = p_final
         x.bom_id = bom
         x.product_qty = 5
-        x.product_uom_id = self.uom_unit
         x.save().action_unbuild()
 
         # Check quantity in stock after last unbuild.
@@ -128,14 +125,12 @@ class TestUnbuild(TestMrpCommon):
             x.product_id = p_final
             x.bom_id = bom
             x.product_qty = 3
-            x.product_uom_id = self.uom_unit
             unbuild_order = x.save()
 
         x = Form(self.env['mrp.unbuild'])
         x.product_id = p_final
         x.bom_id = bom
         x.product_qty = 3
-        x.product_uom_id = self.uom_unit
         x.lot_id = lot
         x.save().action_unbuild()
 
@@ -148,7 +143,6 @@ class TestUnbuild(TestMrpCommon):
         x.bom_id = bom
         x.product_qty = 2
         x.lot_id = lot
-        x.product_uom_id = self.uom_unit
         x.save().action_unbuild()
 
         self.assertEqual(self.env['stock.quant']._get_available_quantity(p_final, self.stock_location, lot_id=lot), 0, 'You should have 0 finalproduct in stock')
@@ -160,7 +154,6 @@ class TestUnbuild(TestMrpCommon):
         x.bom_id = bom
         x.product_qty = 5
         x.lot_id = lot
-        x.product_uom_id = self.uom_unit
         x.save().action_unbuild()
 
         self.assertEqual(self.env['stock.quant']._get_available_quantity(p_final, self.stock_location, lot_id=lot, allow_negative=True), -5, 'You should have negative quantity for final product in stock')
@@ -213,7 +206,6 @@ class TestUnbuild(TestMrpCommon):
         x.product_id = p_final
         x.bom_id = bom
         x.product_qty = 3
-        x.product_uom_id = self.uom_unit
         unbuild_order = x.save()
 
         # This should fail since we do not provide the MO that we wanted to unbuild. (without MO we do not know which consumed lot we have to restore)
@@ -232,7 +224,6 @@ class TestUnbuild(TestMrpCommon):
         x = Form(self.env['mrp.unbuild'])
         x.product_id = p_final
         x.bom_id = bom
-        x.product_uom_id = self.uom_unit
         x.mo_id = mo
         x.product_qty = 2
         x.save().action_unbuild()
@@ -244,7 +235,6 @@ class TestUnbuild(TestMrpCommon):
         x = Form(self.env['mrp.unbuild'])
         x.product_id = p_final
         x.bom_id = bom
-        x.product_uom_id = self.uom_unit
         x.mo_id = mo
         x.product_qty = 5
         x.save().action_unbuild()
@@ -307,14 +297,12 @@ class TestUnbuild(TestMrpCommon):
         with self.assertRaises(AssertionError):
             x.product_id = p_final
             x.bom_id = bom
-            x.product_uom_id = self.uom_unit
             x.product_qty = 3
             x.save()
 
         with self.assertRaises(AssertionError):
             x.product_id = p_final
             x.bom_id = bom
-            x.product_uom_id = self.uom_unit
             x.product_qty = 3
             x.save()
 
@@ -323,7 +311,6 @@ class TestUnbuild(TestMrpCommon):
         with self.assertRaises(AssertionError):
             x.product_id = p_final
             x.bom_id = bom
-            x.product_uom_id = self.uom_unit
             x.mo_id = mo
             x.product_qty = 3
             x.save()
@@ -333,7 +320,6 @@ class TestUnbuild(TestMrpCommon):
         x = Form(self.env['mrp.unbuild'])
         x.product_id = p_final
         x.bom_id = bom
-        x.product_uom_id = self.uom_unit
         x.mo_id = mo
         x.product_qty = 3
         x.lot_id = lot_final
@@ -346,7 +332,6 @@ class TestUnbuild(TestMrpCommon):
         x = Form(self.env['mrp.unbuild'])
         x.product_id = p_final
         x.bom_id = bom
-        x.product_uom_id = self.uom_unit
         x.mo_id = mo
         x.product_qty = 2
         x.lot_id = lot_final
@@ -359,7 +344,6 @@ class TestUnbuild(TestMrpCommon):
         x = Form(self.env['mrp.unbuild'])
         x.product_id = p_final
         x.bom_id = bom
-        x.product_uom_id = self.uom_unit
         x.mo_id = mo
         x.product_qty = 5
         x.lot_id = lot_final
@@ -417,7 +401,6 @@ class TestUnbuild(TestMrpCommon):
         x = Form(self.env['mrp.unbuild'])
         x.product_id = p_final
         x.bom_id = bom
-        x.product_uom_id = self.uom_unit
         x.mo_id = mo
         x.product_qty = 5
         x.save().action_unbuild()
@@ -580,7 +563,6 @@ class TestUnbuild(TestMrpCommon):
         x = Form(self.env['mrp.unbuild'])
         x.product_id = finshed_product
         x.bom_id = bom
-        x.product_uom_id = self.uom_unit
         x.mo_id = mo
         x.product_qty = 1
         x.location_id = self.stock_location
diff --git a/addons/mrp/views/mrp_production_views.xml b/addons/mrp/views/mrp_production_views.xml
index 3c1766a5dd7..2aa12daf471 100644
--- a/addons/mrp/views/mrp_production_views.xml
+++ b/addons/mrp/views/mrp_production_views.xml
@@ -66,6 +66,7 @@
                     <button name="action_cancel" type="object" string="Cancel"
                             attrs="{'invisible': ['|', '|', '|', ('id', '=', False), ('is_locked', '=', False), ('state', 'in', ('done','cancel')), ('confirm_cancel', '=', False)]}"
                             confirm="Some product moves have already been confirmed, this manufacturing order can't be completely cancelled. Are you still sure you want to process ?"/>
+                    <button name="button_unbuild" type="object" string="Unbuild" attrs="{'invisible': [('state', '!=', 'done')]}"/>
                 </header>
                 <sheet>
                     <field name="reservation_state" invisible="1"/>
diff --git a/addons/mrp/views/mrp_unbuild_views.xml b/addons/mrp/views/mrp_unbuild_views.xml
index 4b9590da780..ab4df3167cd 100644
--- a/addons/mrp/views/mrp_unbuild_views.xml
+++ b/addons/mrp/views/mrp_unbuild_views.xml
@@ -114,8 +114,8 @@
                                 <field name="bom_id" attrs="{'readonly':[('mo_id','!=',False)]}" force_save="1"/>
                                 <label for="product_qty"/>
                                 <div class="o_row">
-                                    <field name="product_qty"/>
-                                    <field name="product_uom_id" options="{'no_open':True,'no_create':True}" groups="uom.group_uom"/>
+                                    <field name="product_qty" attrs="{'readonly': [('has_tracking', '=', 'serial')]}"/>
+                                    <field name="product_uom_id" options="{'no_open': True, 'no_create': True}" groups="uom.group_uom" attrs="{'readonly': [('mo_id', '!=', False)]}" force_save="1"/>
                                 </div>
                             </group>
                             <group>