The present disclosure relates to an airbag apparatus for a vehicle, which includes: an airbag cushion which is inflated and deployed in a forward direction from both sides of a passenger upon vehicle collision to protect both sides of the passenger; and an inflater configured to generate gas by an impact detection signal and to supply the gas to the airbag cushion, wherein the airbag cushion includes a first airbag configured to protect both sides or one side from passenger's shoulder to passenger's lower body part; and a second airbag configured to protect passenger's head and both sides of passenger's shoulder, and can restrict and protect passenger's upper body and lower body by inflating and deploying the first and second airbags toward both sides of the passenger upon vehicle collision.