An axle driving apparatus for a vehicle includes an axle, a vertical pump shaft, a hydraulic pump having a movable swash plate, a pair of trunnion shafts provided coaxially at respective opposite sides of the movable swash plate, a hydraulic motor having a motor shaft drivingly connected to the axle, and a housing containing the hydraulic pump, the hydraulic motor, and the axle. The housing includes a first housing member and a second housing member separably jointed along a vertical plane perpendicular to a rotary axis of the axle. A rotary axis of the hydraulic pump is substantially parallel to the vertical plane. The hydraulic pump is entirely disposed in the first housing member. A rotary axis of the trunnion shafts is substantially perpendicular to the vertical plane. One of the trunnion shafts is rotatably supported by the first housing member and the other of the trunnion shafts is rotatably supported by the second housing member, whereby the movable swash plate is slantingly rotatably supported in the housing.