A power system for a hybrid vehicle, the power system including an engine, a first motor, a second motor, a first planetary gear mechanism, a first input shaft, a first clutch, a second clutch, and a brake; the engine is in transmission connection with the first motor, and the first clutch is arranged between the first motor and the first input shaft to cut off or connect power transmission between the first motor and the first input shaft through the first clutch; the first planetary gear mechanism includes a first sun gear, at least one set of planetary gears, a first gear ring, and a first planetary carrier, the first sun gear is arranged on the first input shaft to enable the first sun gear to rotate with the first input shaft, and the first gear ring is configured to transmit power output by the power system; the brake is arranged between the first planetary carrier and a housing of the power system, and the brake is engaged to realize a first gear of the power system; the second clutch is configured to enable the first planetary carrier to rotate with the first input shaft when the second clutch is in an engaged state, to realize a second gear of the power system; and the second motor is connected to the first input shaft and is configured to drive the first input shaft to rotate; characterized in that the power system further includes a second planetary gear mechanism, the second motor is connected to the first input shaft through the second planetary gear mechanism, and the second planetary gear mechanism includes a second sun gear, at least one set of planetary gears, a second gear ring, and a second planetary carrier; and the power system further includes an intermediate support fixedly installed at one end of a front housing close to the first planetary gear mechanism, a cavity structure for installing the brake and a third actuator cylinder corresponding to the brake is formed between the intermediate support and a rear end of the front housing, the first gear ring is in transmission connection with an output gear of the power system, the output gear is supported on the intermediate support through a first support bearing, and the intermediate support is supported on the first planetary carrier through a sliding bearing. the engine is in transmission connection with the first motor, and the first clutch is arranged between the first motor and the first input shaft to cut off or connect power transmission between the first motor and the first input shaft through the first clutch; the first planetary gear mechanism includes a first sun gear, at least one set of planetary gears, a first gear ring, and a first planetary carrier, the first sun gear is arranged on the first input shaft to enable the first sun gear to rotate with the first input shaft, and the first gear ring is configured to transmit power output by the power system; the brake is arranged between the first planetary carrier and a housing of the power system, and the brake is engaged to realize a first gear of the power system; the second clutch is configured to enable the first planetary carrier to rotate with the first input shaft when the second clutch is in an engaged state, to realize a second gear of the power system; and the second motor is connected to the first input shaft and is configured to drive the first input shaft to rotate; characterized in that the power system further includes a second planetary gear mechanism, the second motor is connected to the first input shaft through the second planetary gear mechanism, and the second planetary gear mechanism includes a second sun gear, at least one set of planetary gears, a second gear ring, and a second planetary carrier; and the power system further includes an intermediate support fixedly installed at one end of a front housing close to the first planetary gear mechanism, a cavity structure for installing the brake and a third actuator cylinder corresponding to the brake is formed between the intermediate support and a rear end of the front housing, the first gear ring is in transmission connection with an output gear of the power system, the output gear is supported on the intermediate support through a first support bearing, and the intermediate support is supported on the first planetary carrier through a sliding bearing.