An occupant protection system for vehicle, includes an own-vehicle information acquisition unit acquiring an own-vehicle information including a route information on a course of an own vehicle to a destination, an other-vehicle information acquisition unit acquiring other-vehicle information that is received through vehicle-to-vehicle communication and that includes position information of another vehicle, a crash condition calculation unit calculating a crash condition between the own vehicle and said another vehicle on the basis of the own-vehicle information and other-vehicle information, and an operation preparation unit preparing a system which corresponds to a crash damage decreasing system decreasing a level of a crash damage of an occupant of the own vehicle, and which is adapted to decrease the level of the crash damage that corresponds to the crash condition calculated by the crash condition calculation unit to operate.