Transmission for working vehicles having forcedly driven rear wheels (2) as well as rear-PTO shaft (17) and mid-PTO shaft (19) for driving working implements is disclosed. The transmission includes a hydrostatic transmission (7) fixedly provided on the front of transmission case (8) so as to use pump shaft (23) thereof for the input of working implement-driving power at a high level into transmission case (8) from which the rear-PTO shaft (17) extends backwardly at a middle level and so as to permit a low level arrangement of the mid-PTO shaft (19). Within the transmission case (8), clutch means (31, 36) and speed-change means (32) for PTO-line are arranged at an upper half whereas speed-change gearing (43) and differential gearing (44) for vehicle drive line are arranged at a lower half by employing motor shaft (22) of the hydrostatic transmission as input shaft. A compact arrangement of transmission components is achieved so that transmission case (8) may be reduced in length as well as in weight.