The invention relates to the technical field of transmission, in particular to a transmission structure which comprises a first side plate, a second side plate and a transverse plate connected with the first side plate and the second side plate. A hydraulic cylinder is fixedly arranged on the first side plate, a first fixing sleeve is fixedly arranged on the portion, away from a piston of the hydraulic cylinder, of the first side plate, the second side plate is provided with a sleeve, the sleeve is located on the inner side of the second side plate, the sleeve is provided with a gap formed inthe axial direction of the sleeve, a sliding rod is arranged in the sleeve in a sliding mode, and a rack is fixedly arranged on the sliding rod. The structure is simple, when a piston rod of the hydraulic cylinder is extended, an output shaft of a one-way clutch is rotated, when the piston rod of the hydraulic cylinder is retracted, the output shaft of the one-way clutch is not rotated, and characteristic using conditions can be met.