Water contained in exhaust gas discharged from a fuel cell stack is separated by a gas-liquid separator and is accumulated in a recovery tank. The procedure of the invention sets a release amount of water and selects one or multiple positions for water release, based on the driving conditions including the vehicle speed and the acceleration, the turning state, activation or non-activation of skid reduction control, the distance from any object detected by clearance sonars, a distance from a subsequent vehicle measured by an extremely high frequency radar, and the presence of raindrops detected by a raindrop detection sensor, and releases the water accumulated in the recovery tank from water outlets at the selected one or multiple positions among water outlets at multiple different locations. This arrangement ensures adequate release of the water produced by the fuel cell stack to the atmosphere.