A bumper assembly for vehicle may include a first side member disposed in each of both sides of a vehicle body in a longitudinal direction thereof, a second side member coupled to an external surface of the first side member, a fender member having one side coupled to an external side of the second side member, a member flange connected to front ends of the first and second side members respectively, a mounting flange coupled with the member flange, a first crash box having a rear end connected to the mounting flange, a second crash box having a rear end connected to the mounting flange, and a bumper beam having both distal sides, each of which may be coupled to front ends of the first and second crash boxes.