A power transmission apparatus includes an oil pump disposed between a hydraulic controller and a strainer. The oil pump includes a rotor (3) and a housing provided with a rotor chamber housing the rotor (3). Rotation of the rotor (3) causes oil to be sucked into an oil chamber (c1) defined by the rotor (3), and the oil is pressurized and discharged therefrom. The housing is provided with a first oil passage (71) through which oil sucked from a reservoir through the strainer flows toward the oil chamber, and a second oil passage (72) through which oil refluxed from the hydraulic controller flows toward the oil chamber. The second oil passage (72) includes a curved oil passage curved along the rotor (3) and is disposed such that the oil refluxed from the hydraulic controller flows in a rotation direction of the rotor (3) through the curved oil passage.