Operating mechanism, gearbox and vehicle

The utility model provides an operating mechanism, a gearbox and a vehicle. The operating mechanism comprises a first shell, a gear selecting shaft and a gear selecting arm. The gear selecting shaft comprises a body and a positioning part, the positioning part is connected with one end of the body, and the other end of the body extends into the shell; a through hole is formed in the gear selectingarm, and the positioning part is inserted into the through hole; wherein the cross section of the positioning part is non-circular, and the shape of the through hole is matched with the shape of thecross section of the positioning part. Due to the fact that the positioning part is inserted into the through hole of the gear selecting arm, the gear selecting shaft and the gear selecting arm are detachable, when the control mechanism is maintained, the gear selecting arm can be detached firstly, then the first shell is opened, the control mechanism can be maintained, and the maintenance difficulty of the control mechani