An in-wheel motor drive device comprising a lubricating oil supply structure, the in-wheel motor drive device comprising: a motor unit including a stator core and a pair of coil ends disposed on either side of the stator core to drive a wheel; a wheel hub bearing unit; and a reducer unit having a plurality of gears (33, 34, 36, 37, 39, 40), the reducer unit configured to reduce rotation of the motor unit and transmit that rotation to the wheel hub bearing unit, the lubricating oil supply structure comprising: an oil tank provided at, when in use, a lower part of the motor unit and/or the reducer unit, being configured to store lubricating oil; an oil pump configured to pump up lubricating oil from the oil tank; and an oil pipe (70, 70A, 70B) fixedly attached to, when in use, an upper part of the motor unit and the reducer unit, wherein the oil pipe (70, 70A, 70B) includes an inlet through which lubricating oil pumped up from the oil pump flows therein, and a plurality of outlets provided between one end thereof and the other end thereof, the plurality of outlets configured to discharge the lubricating oil flown into the oil pipe (70, 70A, 70B) from the inlet downwards, characterized in that an internal space in the motor unit and an internal space in the reducer unit are partitioned by a partition, the oil pipe (70, 70A, 70B) is inserted through the partition and extends in an axle direction, and includes a first portion located at an upper part of the internal space in the motor unit and a second portion located at an upper part of the internal space in the reducer unit, and the plurality of outlets include outlets provided at least at positions facing the coil ends in the first portion and at least one outlet provided at a position facing outer peripheral surface of at least one of the gears (33, 34, 36, 37, 39, 40) in the second portion. an oil tank provided at, when in use, a lower part of the motor unit and/or the reducer unit, being configured to store lubricating oil; an oil pump configured to pump up lubricating oil from the oil tank; and an oil pipe (70, 70A, 70B) fixedly attached to, when in use, an upper part of the motor unit and the reducer unit, wherein the oil pipe (70, 70A, 70B) includes an inlet through which lubricating oil pumped up from the oil pump flows therein, and a plurality of outlets provided between one end thereof and the other end thereof, the plurality of outlets configured to discharge the lubricating oil flown into the oil pipe (70, 70A, 70B) from the inlet downwards, characterized in that an internal space in the motor unit and an internal space in the reducer unit are partitioned by a partition, the oil pipe (70, 70A, 70B) is inserted through the partition and extends in an axle direction, and includes a first portion located at an upper part of the internal space in the motor unit and a second portion located at an upper part of the internal space in the reducer unit, and the plurality of outlets include outlets provided at least at positions facing the coil ends in the first portion and at least one outlet provided at a position facing outer peripheral surface of at least one of the gears (33, 34, 36, 37, 39, 40) in the second portion.