To provide an environment-friendly cooling system for a vehicle for cooling a stack of a fuel cell vehicle and electric power parts.

This environment-friendly cooling system includes: an integrated radiator through which all of working fluid for cooling the electric power parts and working fluid for cooling an air conditioner condenser passes to be cooled; a pump arranged in series with the integrated radiator so that the working fluid of the integrated radiator may be pumped to the electric power parts or the air conditioner condenser; a first branch pipe and a second branch pipe for connecting the electric power parts and the water-cooled air conditioner condenser in parallel in relation to the integrated radiator and the pump; and a valve device installed to supply coolant from the coolant pump to the first branch pipe and the second branch pipe by adjusting the coolant.