A power system for a hybrid vehicle, the power system includes an engine, a first motor, a second motor, a first planetary gear mechanism, an input shaft, a first clutch, a second clutch, and a first brake; the engine is connected to the first motor, and the first clutch is arranged between the first motor and the input shaft to cut off or connect power transmission between the first motor and the input shaft through the first clutch; the second motor is arranged on the input shaft to drive the input shaft to rotate; the first planetary gear mechanism includes a first sun gear, a first set of planetary gears, a first gear ring and a first planetary carrier, and the first sun gear is arranged on the input shaft to enable the first sun gear to rotate with the input shaft; characterized in that the first planetary gear mechanism further includes a second set of planetary gears, and the first planetary carrier is shared by the first set of planetary gears and the second set of planetary gears; external gears of the second set of planetary gears are respectively meshed with external gears of the first set of planetary gears and an internal gear of the first gear ring, and the first gear ring is configured to transmit power output by the power system; the first brake is arranged between the first planetary carrier and a housing of the power system; the first planetary gear mechanism further includes a second sun gear coaxial with the first sun gear, the second sun gear and the input shaft are independent of each other, and an external gear of the second sun gear is meshed with the external gears of the second set of planetary gears; the power system further includes a second brake; the second brake is configured to fix the second sun gear when the second brake is in a braking state, to enable the second sun gear to remain relatively static with the housing of the power system; and the second clutch is configured to enable the second sun gear to rotate with the input shaft when the second clutch is in an engaged state; and the second motor is connected to the input shaft through a second planetary gear mechanism, and the second planetary gear mechanism includes a third sun gear, at least one set of planetary gears, a second gear ring, and a second planetary carrier. the engine is connected to the first motor, and the first clutch is arranged between the first motor and the input shaft to cut off or connect power transmission between the first motor and the input shaft through the first clutch; the second motor is arranged on the input shaft to drive the input shaft to rotate; the first planetary gear mechanism includes a first sun gear, a first set of planetary gears, a first gear ring and a first planetary carrier, and the first sun gear is arranged on the input shaft to enable the first sun gear to rotate with the input shaft; characterized in that the first planetary gear mechanism further includes a second set of planetary gears, and the first planetary carrier is shared by the first set of planetary gears and the second set of planetary gears; external gears of the second set of planetary gears are respectively meshed with external gears of the first set of planetary gears and an internal gear of the first gear ring, and the first gear ring is configured to transmit power output by the power system; the first brake is arranged between the first planetary carrier and a housing of the power system; the first planetary gear mechanism further includes a second sun gear coaxial with the first sun gear, the second sun gear and the input shaft are independent of each other, and an external gear of the second sun gear is meshed with the external gears of the second set of planetary gears; the power system further includes a second brake; the second brake is configured to fix the second sun gear when the second brake is in a braking state, to enable the second sun gear to remain relatively static with the housing of the power system; and the second clutch is configured to enable the second sun gear to rotate with the input shaft when the second clutch is in an engaged state; and the second motor is connected to the input shaft through a second planetary gear mechanism, and the second planetary gear mechanism includes a third sun gear, at least one set of planetary gears, a second gear ring, and a second planetary carrier.