A far-side airbag apparatus comprising: a gas generator, and an airbag comprising a fixed portion set in a rear end portion of the airbag and disposed to incline such that the upper side of the fixed portion is positioned close to the rear side, wherein the airbag is configured to be deployed and inflated diagonally forward and upward from the fixed portion in order to protect, when mounted in a vehicle, an upper body of an occupant, who sits on a vehicle seat positioned apart from a side wall portion of the vehicle in which multiple vehicle seats are provided side by side in a width direction, by deploying and inflating the airbag diagonally forward and upward from the fixed portion between adjacent vehicle seats via inflating gas which is supplied from the gas generator according to a side impact applied to the side wall portion of the vehicle, wherein a rear lower portion of the airbag is formed as a support portion that has a high rigidity and supports an upper portion positioned higher than the rear lower portion of the airbag, as thickness restriction portions which restrict the inflation thickness of the airbag, multiple partition portions are provided in the upper portion of the airbag, and partition the upper portion into multiple regions, the multiple partition portions are provided in a front region and a rear region which are respectively positioned in front of and in back of a central portion of the upper portion in a forward and rearward direction, rigidity of the support portion is increased by not providing a partition portion in the support portion, the airbag includes a pair of side fabric portions (42, 43) which are disposed in the vehicle width direction, the partition portions are formed integrally with both of the side fabric portions by weaving, and the multiple partition portions (55, 56) are provided in the upper portion of the airbag and extend in a vertical direction. a gas generator, and an airbag comprising a fixed portion set in a rear end portion of the airbag and disposed to incline such that the upper side of the fixed portion is positioned close to the rear side, wherein the airbag is configured to be deployed and inflated diagonally forward and upward from the fixed portion in order to protect, when mounted in a vehicle, an upper body of an occupant, who sits on a vehicle seat positioned apart from a side wall portion of the vehicle in which multiple vehicle seats are provided side by side in a width direction, by deploying and inflating the airbag diagonally forward and upward from the fixed portion between adjacent vehicle seats via inflating gas which is supplied from the gas generator according to a side impact applied to the side wall portion of the vehicle, wherein a rear lower portion of the airbag is formed as a support portion that has a high rigidity and supports an upper portion positioned higher than the rear lower portion of the airbag, as thickness restriction portions which restrict the inflation thickness of the airbag, multiple partition portions are provided in the upper portion of the airbag, and partition the upper portion into multiple regions, the multiple partition portions are provided in a front region and a rear region which are respectively positioned in front of and in back of a central portion of the upper portion in a forward and rearward direction, rigidity of the support portion is increased by not providing a partition portion in the support portion, the airbag includes a pair of side fabric portions (42, 43) which are disposed in the vehicle width direction, the partition portions are formed integrally with both of the side fabric portions by weaving, and the multiple partition portions (55, 56) are provided in the upper portion of the airbag and extend in a vertical direction.