To provide an oil pump structure of an automatic transmission which prevents damage to a bushing by heat shrinkage.

The oil pump structure of the automatic transmission includes: a cylindrical torque converter sleeve 20, the base end of which is fixed to a pump impeller 22 of a torque converter 2; a cylindrical bushing 10, which is fitted externally to the torque converter sleeve 20; and an oil pump 3, on which the torque converter sleeve 20 is supported via the bushing 10. In this structure, the bushing 10 is integrated by being press fitted into a bushing receiving cylinder 30 formed in a thick wall cylindrical shape of a material equivalent to that of the torque converter sleeve 20. This integrated bushing receiving cylinder 30 is press fitted to a bearing portion 3a of the oil pump 3 to support the torque converter sleeve 20.