A swash plate type hydraulic pump and a swash plate type hydraulic motor in formed in combination to reduce the amount of oil leakage and to increase efficiency in a hydrostatic continuously variable transmission. A hydrostatic continuously variable transmission including a swash plate type hydraulic pump, a swash plate type hydraulic motor, and a hydraulic closed circuit disposed between the hydraulic pump and the hydraulic motor. The hydraulic pump is integrally combined with the hydraulic motor by an output shaft press-fitted in a cylinder block B in which pump cylinder bores and motor cylinder bores are formed in parallel to the output shaft. The diameters of back portions of the pump cylinder bore and the motor cylinder bore are larger relative to the diameters of entry portions to the pump cylinder bore and the motor cylinder bore. Wherein a press-fitting portion is not provided at the contact portions inside the entry portions with the output shaft.