A separable point of sale system includes a mainframe and a base. The mainframe has one or more base connecting sockets, a case, a touch screen and a power receiving socket, and the case has a mainframe tenon; the base has an inputting module, one or more mainframe connecting plugs, a base tenon, a power supply plug and a trough used to accommodate the mainframe. The base tenon operatively connects with the mainframe tenon, and the amount of the mainframe connecting plugs and that of the base connecting sockets are the same. When the mainframe tenon connects with the base tenon, the mainframe is vertically placed in the trough. Because the disposition of the power supply plug and the mainframe connection plugs corresponds to that of power receiving socket and the base connection sockets, therefore, as the mainframe tenon connects with the base tenon, the power receiving socket has electrical connection with the power supply plug, and the base connecting sockets have electrical connection with the mainframe connecting plugs, too.