PURPOSE: To enable the optimum correction corresponding to the driving state without a special sensor by enumerating the correction quantity according to the load detected by the deviation between an unloaded engagement starting clutch position and an actual engagement starting clutch position, thereby correcting a semi-clutch target clutch position.

CONSTITUTION: In a semi-clutch control process where an actual clutch position S proceeds to a semi-clutch target clutch position SD2 from a minimum target clutch position SD1 at the time of startup, the rise of the primary pulley rotating speed Np on the clutch output side is detected, and a clutch position at the time of obtaining Np>0 at the actual engagement starting point corresponding to travel load is detected. The deviation S corresponding to the travel load is then enumerated from a clutch position at an unloaded engagement starting point and the actual engagement starting clutch position. A correction factor (k) is also set from the throttle opening θ at the time of this startup so as to enumerate the correction quantity k.S, thus correcting the semi-clutch target clutch position SD2.