An airbag of an airbag device for a front passenger seat includes a passenger-side wall, a circumferential wall, a gas inlet port disposed in a vicinity of the front end of the airbag as deployed, a bottom pocket that is recessed upward from a lower region of the circumferential wall in such a manner as to be continuous with the lower region, and a tether that is disposed generally along a front and rear direction inside the airbag and connects the passenger-side wall and a vicinity of the gas inlet port. The bottom pocket is formed into a pouch like contour by joining outer circumferential edges of left and right bottom pocket constituent regions that extend from the lower region of the circumferential wall. The upper end region of the bottom pocket is joined to the tether.