WORK VEHICLE

An attachment device (2) includes a support table member (6) and a coupling mechanism (20). The coupling mechanism (20) includes a coupling bolt (21) and an abutment member (22) having a nut portion (23). In the abutment member (22), there is formed a locking protrusion (24) protruding to the side where an auxiliary machine fixing portion (54) is present. In the auxiliary machine fixing portion (54), there are formed an insertion hole (54a) for the coupling bolt (21) and an anti-rotation hole (54b) in which the locking protrusion (24) can be fitted.