A strobo control circuit for a program shutter which opens or closes sectors by means of a stepping motor, wherein a data ROM (read-only memory) is accessed in accordance with a value obtained by computing a code representative of a distance to a subject, a film speed and so forth, and after the data stored in the ROM is set in a timer circuit, the timer is started synchronously with start of the stepping motor to produce a strobo trigger signal upon termination of the timer action.