A control system of a hybrid vehicle, in which a driving power source for travel includes an engine that is started by cranking, a motor that can control a torque, and a clutch that is coupled with the motor and in which a transmission torque capacity continuously changes depending on a change of a control amount is configured to estimate (steps S2 and S3) a torque of the clutch based on the torque that the motor outputs, and change rates of the rotational speed of the motor and the clutch caused by changing the control amount, when the torque that the motor outputs is transmitted by the clutch that is in a slip state by changing the control amount.