A vehicle mount structure for includes a stack case and a boss. The stack case accommodates a fuel cell stack. The stack case includes a bottom panel to be provided on a bracket member of a vehicle. The bottom panel includes a lower plate and an intermediate member. The lower plate is opposite to and below an upper plate in a height direction of the vehicle. The lower plate has an opening to surround a bearing surface of the bracket member. The intermediate member is disposed between the upper plate and the lower plate. The intermediate member has a thickness thicker than a thickness of the upper plate and a thickness of the lower plate. The boss is disposed on the intermediate member and includes a rib. The boss with the rib protrudes toward the bracket member to pass through the opening.