diff --git a/addons/purchase/views/account_invoice_views.xml b/addons/purchase/views/account_invoice_views.xml
index 7f4fc3bf4e0..3f23f6777d0 100644
--- a/addons/purchase/views/account_invoice_views.xml
+++ b/addons/purchase/views/account_invoice_views.xml
@@ -59,7 +59,7 @@
         <field name="inherit_id" ref="account.invoice_supplier_form"/>
         <field name="arch" type="xml">
             <field name="reference" position="after" >
-                 <field name="purchase_id" attrs="{'invisible': [('state', '=', 'purchase')]}" class="oe_edit_only" 
+                 <field name="purchase_id" attrs="{'readonly': [('state','not in',['draft'])], 'invisible': [('state', '=', 'purchase')]}" class="oe_edit_only"
                     options="{'no_create': True}"/>
             </field>
             <xpath expr="//field[@name='invoice_line_ids']/tree/field[@name='company_id']" position="after">