Disclosed is an idle stop control device capable of relieving reaction force (kickback) of a handle occurring at idle stop controlled by the control of the idle stop control device. Specifically, an EPSECU (20) detects the rotational speed of an electric motor by detecting the rotational angle (θm) of the electric motor using a resolver (22), and at the same time, detects the steering torque using a torque sensor (23). Subsequently, the EPSECU determines whether or not the rotational speed of the electric motor and the steering torque are inside an idle stop transition area (P) by referring to a table (28) stored in a memory (27) in advance. When either or both of the rotational speed of the electric motor and the steering torque are outside the idle stop transition area (P), a signal requesting the prohibition of idle stop transition is output to an idle stop control device (10) via a cable (15). Upon receiving the signal requesting the prohibition of idle stop transition, the idle stop control device (10) prohibits the control of transition to idle stop even when conditions for idle stop are met.