PURPOSE: To make a rear PTO shaft at not only live speed but also at ground speed by dividing the PTO into two shafts on the upper stream of a relay gear and making both shafts disengage from each other and make the relay gear and second shaft disengage.

CONSTITUTION: The relay gear 34 of the two stage gear engaging the drive gear 33 of a differential drive shaft 28 is revolvably provided around a transmission shaft 26 for PTO, which is divided into first and second shafts 26A and 26B, which are connected by a faucet joint 26C. In addition, a clutch member 35 disengaging the spline 34A of the relay gear 34 and the spline 26E of the second shaft 26, splines 26D, and 26E are provided. When a shift gear 39 engages with the relay gear 34, the speed of a mid PTO shaft 36 becomes ground speed which synchronize with the differential drive shaft 28. Therefore, a rear PTO shaft 27 can easily and simply rotate at live speed and ground speed.