PURPOSE: To simplify the simultaneous call connection, by providing a device, where storage positions of subscribes called simultaneously by a call number and information of the connection state of every trunk are stored, in a control device in a stored program electronic exchange.

CONSTITUTION: When a simultaneous connection number and a pattern number are dialed after an originating subscriber A has hooked off and has been connected to an outgoing register trunk ORT, this information is sent from the ORT to a central control device CP through a trunk control device TKC. When discriminating the simultaneous connection number, the control device CP expands the pattern number and searches an address of a storage device MU, where a called subscriber of the number is stored, to discriminate a corresponding address and reads out contents in this address in order to discriminate simultaneous connection subscribers B and C. Next, the control device CP reserves an intra-office trunk IOT and connects two call signal transmitting trunks RGT to the called subscriber to call him, and the simultaneous connection is performed through the trunk IOT by the response of the other party.