A vehicle gas processing device is configured to supply gas generated by a vehicle to an intake pipe of a combustion engine. The device may includes: a gas pipe configured to communicate a gas generation source to the intake pipe, the gas pipe having a flexible end at least at an intake pipe side of the gas pipe; a check valve disposed between the intake pipe and the gas pipe, and configured to allow the gas to flow from the gas pipe toward the intake pipe and prohibit the gas to flow from the intake pipe toward the gas pipe; and a determining unit configured to determine that the gas pipe is detached from the check valve. The check valve is fixed to the intake pipe, and the gas pipe is detachably attached to the check valve.