A control system for hybrid vehicle (Ve) to eliminate the shortage of drive force within the low-to-mid speed range in the hybrid mode. In a differential mechanism (5, 30, 40, 50, 60, 70, 80), a first rotary element (5a, 30a, 40a, 50a, 60a, 70a, 80a) is connected to an engine (1), a second rotary element (5b, 30b, 40b, 50b, 60b, 70b, 80b) is connected to a first motor (2), a third rotary element (5c, 30c, 40c, 50c, 60c, 70c, 80c) is connected to a second motor (3), and a fourth rotary element (5d, 30d, 40d, 50d, 60d, 70d, 80d) is connected to an output unit (7, 201, 221). A third motor (4) is connected to the output unit (202, 222). When the controller (11) determines that the hybrid vehicle (Ve) is propelled by the torque of the engine (1), the first motor (2) and the second motor (3) generate torques in a same direction as an engine torque to propel the vehicle (Ve) in a forward direction, and the third motor (4) generates a torque in the forward direction to propel the vehicle (Ve) together with the engine torque.