The invention discloses a planet type double-mode hybrid power system of a birotor motor. The planet type double-mode hybrid power system consists of an engine, a first motor, a second motor, a front planet set, a rear planet set, an output gear, an inverter, a super-capacitor and a locker, wherein the second motor is a birotor motor which comprises an inner rotor, a stator and an outer rotor; the front planet set comprises a front set solar wheel, a front set planet carrier, a front set planet wheel and a front set gear ring; the rear planet set comprises a rear set solar wheel, a rear set planet carrier, a rear set planet wheel and a rear set gear ring. The birotor motor is adopted to achieve double modes, so that the structure is simple and compact; the system is easy to control and relatively low in cost as only one locker is adopted; under the condition of identical requirements on vehicle properties, the second motor, which is relatively small in peak value torque and peak value rotation speed, can be used, and the requirements of the system on the driving motors can be reduced; the first motor can be locked when achieving the zero rotation speed, so that low-efficiency operation of the first motor is avoided, and the efficiency of the system is improved; as the birotor motor is adopted, and the inner rotor and the outer rotor can participate in regeneration brake simultaneously, the brake energy can be relatively effectively recycled.