An access control system includes a mobile device, a control device and an electronic lock module. The mobile device includes an input module, an identification module, a display module, a storage module, a battery module, a wireless transmission module and a central processor. The control device connects with the mobile device wirelessly and includes a wireless transceiver module, a power module, a memory module, an electronic control module and a microcontroller. The electronic control module of the control device is electrically connected with the electronic lock device. The identification module captures the biological characteristic of the user so as to make the identification module identify the biological characteristic of the user, so as to lower an identification burden of the access control system and ensure a usage security of the access control system.