A connector for medical liquid-containing packages, comprises a connecting element (1) with a channel-shaped recess (1c) containing a self-sealing membrane (8), the recess being closed by a breakable part (17) connected to a connecting piece. Above the membrane, there is a connecting piece (13) comprising an internal cone (14) and an external thread (15), and the membrane is sealed for reception of a syringe cone shaft. An independent claim is also included for a packaging for medical liquids, especially infusion and transfusion bags with a connector (claimed).