Hi,

try something like this (not tested) :

def _get_users_group_project(self):
    return [('id', 'in', self.env.ref('xml_id_of_group').users.ids)]

to_approve_by = fields.Many2one('res.users', string='To Approve by', domain=lambda self:self._get_users_group_project())

Regards

Dear Mohammed Amal,

Did your means that I should code my .py file like below?:

to_approve_by = fields.Many2one(comodel_name='res.users',
                                string='To Approve by',
                                domain="[('groups_id.ids','??',??)]")

But I don't know how to code the 'operator' and 'value' section in the tuple. So, Would your please give me a sample?