PURPOSE: To provide a clutch driving device preventing inertial rotation positively so as to reduce the damage of lining material, thereby prolonging a service life.

CONSTITUTION: A gear pump 72 pumps up operating oil in a tank 70 through a filter 71 and discharges it to the change-over valve 73 side. The pressure oil chamber 64 of a brake release hydraulic cylinder 60 is communicated with a pressure oil path 65, and the pressure oil chamber 28 of a clutch driving hydraulic cylinder 29 is communicated with the pressure oil chamber 64 through a connecting line 66. A relief valve 75 is connected between the pressure oil path 65 and the operating oil tank 70. At the clutch cut-off time, the operating oil fed from the change-over valve 73 is fed to the cylinder 29 via the cylinder 60 and the connecting line 66. At the clutch connecting time, the operating oil discharged from the cylinder 29 is discharged to the tank 70 via the connecting line 66 and the cylinder 60.