A hybrid drive device includes a speed change mechanism, a motor drivingly coupled to an input shaft, and a clutch interposed between an engine and an input shaft. Upon engine start during engine traveling, the clutch is engaged, and rotation of the engine is increased. A control device of the hybrid drive device includes start upshift control means that, according to the engagement control of the clutch upon engine start, upshifts the speed change mechanism to output inertia torque. Thus, when the engine is started, output torque as the sum of driving torque of the motor and the inertia torque is output to the driving wheel, which reduces hesitation upon engine start.