An anti-theft means for vehicle steering mechanism, such as a steering shaft or a transmission rod, having a rotatable shaft. The anti-theft means comprises a fixing member fixed on the vehicle body, a connecting member joined with a steering handle, a locking means controlled by code device, a movable member provided on the rotatable shaft, for moving along said shaft but not rotatable around it. The movable member can move between a first position and a second position under the control of the locking means. When in the first position, the movable member is engaged with the fixing member while disengaged with the connecting member so that the shaft can not rotate. When in the second position, the movable member is engaged with the connecting member while disengaged with the fixing member so that the shaft can rotate. The anti-theft means according to the invention has double functions of disconnecting transmission of steering force as well as locking the shaft.