A working vehicle, comprising: a vehicle body ; a driving part ; a hydrostatic transmission which has a hydrostatic transmission trunnion shaft. ; a hydrostatic transmission link mechanism which connects a hydrostatic transmission pedal to the hydrostatic transmission trunnion shaft ; a hydrostatic transmission neutrality-returning cam fixed to the hydrostatic transmission trunnion shaft ; a hydrostatic transmission neutrality-returning arm member which interlocks with the hydrostatic transmission neutrality-returning cam , and rotates around a rotation fulcrum shaft ; and a hydrostatic transmission neutrality-returning spring which energizes the hydrostatic transmission neutrality-returning arm member , so that the hydrostatic transmission trunnion shaft returns to a neutrality position, the hydrostatic transmission trunnion shaft , and the rotation fulcrum shaft are arranged immediately under the hydrostatic transmission pedal , the hydrostatic transmission neutrality returning arm member has a spring joining arm to which the hydrostatic transmission neutrality-returning spring is joined, and a bearing joining arm protrudingly provided to which a cam abutting bearing , which is made to abut against the hydrostatic transmission neutrality-returning cam , is fixed, characterized in that the spring joining arm , a lower-end part of which is joined to the rotation fulcrum shaft , is upwardly provided, so that an upper-end part of the spring joining arm (1.22) is positioned above a floor of the driving part , and the hydrostatic transmission neutrality-returning spring is arranged above the floor of the driving part , so that a front-end part of the hydrostatic transmission neutrality-returning spring is joined tο a stay attached to the vehicle-body and that a rear-end part of the hydrostatic transmission neutrality-returning spring is joined to the upper-end part of the spring joining arm . a vehicle body ; a driving part ; a hydrostatic transmission which has a hydrostatic transmission trunnion shaft. ; a hydrostatic transmission link mechanism which connects a hydrostatic transmission pedal to the hydrostatic transmission trunnion shaft ; a hydrostatic transmission neutrality-returning cam fixed to the hydrostatic transmission trunnion shaft ; a hydrostatic transmission neutrality-returning arm member which interlocks with the hydrostatic transmission neutrality-returning cam , and rotates around a rotation fulcrum shaft ; and a hydrostatic transmission neutrality-returning spring which energizes the hydrostatic transmission neutrality-returning arm member , so that the hydrostatic transmission trunnion shaft returns to a neutrality position, the hydrostatic transmission trunnion shaft , and the rotation fulcrum shaft are arranged immediately under the hydrostatic transmission pedal , the hydrostatic transmission neutrality returning arm member has a spring joining arm to which the hydrostatic transmission neutrality-returning spring is joined, and a bearing joining arm protrudingly provided to which a cam abutting bearing , which is made to abut against the hydrostatic transmission neutrality-returning cam , is fixed, characterized in that the spring joining arm , a lower-end part of which is joined to the rotation fulcrum shaft , is upwardly provided, so that an upper-end part of the spring joining arm (1.22) is positioned above a floor of the driving part , and the hydrostatic transmission neutrality-returning spring is arranged above the floor of the driving part , so that a front-end part of the hydrostatic transmission neutrality-returning spring is joined tο a stay attached to the vehicle-body and that a rear-end part of the hydrostatic transmission neutrality-returning spring is joined to the upper-end part of the spring joining arm . <EOS>