The invention discloses a three-shaft clutch speed change device, which includes a speed change gear set, three clutch devices, at least one and at most three clutches, the speed change gear set includes a first input shaft, a second input shaft and a third input shaft, the first The second input shaft and the third input shaft are hollow shafts, the first input shaft is passed through the second input shaft which is a hollow shaft, the second input shaft is passed through the third input shaft which is a hollow shaft, and the three clutch devices They are respectively connected between the power output shaft and the first input shaft, the second input shaft and the third input shaft; the three clutches are respectively connected to any two of the power input part, power output part and transmission control part of the three clutch devices. Between them, it is used for selective engagement, so that the power drives the input shaft of the variable speed gear set at a constant speed. The invention can meet the multi-gear requirements of the vehicle on the limited structural size.