Abstract: A lock-up clutch control device which controls a lock-up clutch (6) provided in a torque converter (5) interposed between an engine (3) and a transmission (4) used with a vehicle, is disclosed. The lock-up clutch control device has a differential pressure generating device (7,8), a vehicle speed sensor (13), a throttle valve opening sensor (14), an transmission input shaft rotation speed sensor (16), engine torque detection means (2), and a controller (1). The controller (1) determines, based on the detected vehicle speed (VSP) and the detected throttle valve opening (TVO), whether or not a control region of a torque converter is a converter region wherein control is performed to disengage the lock-up clutch.