A rough-terrain traveling vehicle equipped with a front seat roll bar and a rear seat roll bar is adapted to allow use of only the front seat roll bar. The front seat roll bar includes a top middle cross pipe extending left and right in the vehicle width direction, and left and right middle side pipes extending to the top middle cross pipe. Left and right gussets are provided at left and right assembly points where the left and right middle side pipes and the top middle cross pipe each are connected. When attachment screws are inserted into the left and right gussets, the rear seat roll bar is joined to the front seat roll bar.