The utility model discloses a mechanical transmission which comprises an input shaft, a first mesh sleeve, a second mesh sleeve, a clutch, an odd-gear output shaft and an even-gear output shaft. The clutch, the first mesh sleeve, the second mesh sleeve, the odd-gear output shaft and the even-gear output shaft can form a power transmission line, power of the input shaft can be alternatively transmitted to the odd-gear output shaft or the even-gear output shaft by orderly controlling the clutch to be combined and loosened and the first mesh sleeve and the second mesh sleeve to be combined and retreated, and upshift and downshift operation can be finished. The gear shifting operation can be obtained through matched operation among the clutch, the first mesh sleeve and the second mesh sleeve. Thus, the number of clutches in the prior art is reduced, the volume of the transmission is reduced, dragging resistance generated by clutches of an existing transmission is reduced, the transmitting efficiency is improved, and the whole machine production cost of the mechanical transmission is also reduced.