The invention discloses a multi-speed planetary gear type double-
clutch gearbox which comprises a first
clutch, a first input shaft corresponding to the first
clutch, a second clutch, a second input shaft corresponding to the second clutch, a plurality of synchronizers and an output shaft, wherein the first input shaft and the second input shaft are arranged in a sleeving way; the multi-speed planetary gear type double-clutch gearbox also comprises a first double-row planetary
gear train, a second double-row planetary
gear train, a first gear, a second gear, a third gear and a fourth gear, wherein the first gear is meshed with the second gear; the third gear is meshed with the fourth gear; one of the first double-row planetary
gear train and the second double-row planetary gear
train is formed by two
planet rows; in the front
planet row, a front sun gear is connected with a rear
planet carrier into a whole, and is fixed with a shell by the first constant mesh
synchronizer or the clutches; the rear planet row adopts a double-planet wheel structure; a front gear ring is connected with a rear gear ring into a whole; the power is transmitted into a rear sun gear or the rear gear ring by the second
synchronizer, the third
synchronizer or the clutches through a first rear outer shaft, and is output by a front planet carrier. The multi-speed planetary gear type double-clutch gearbox can realize more speed ratio gears by fewer gear pairs, reduces the size of the gearbox, and enables the structural
layout design of an automobile to be more flexible.