To provide a hydraulic continuously variable transmission capable of suppressing seizing of a spool valve and a sleeve and breaking of the spool valve.

A hydraulic continuously variable transmission 10 includes a hydraulic continuously variable transmitting part X connected to an input shaft 20 so that power can be transmitted. The hydraulic continuously variable transmitting part X includes: a cylinder block 30; a plunger 40 for a hydraulic pump; a swash plate 50 for the hydraulic pump; a plunger 60 for a hydraulic motor; and a swash plate 70 for the hydraulic motor. An oil passage 21 is provided inside the input shaft 20. The cylinder block 30 has a built-in spool valve 90 for pump and a built-in spool valve 92 for motor, and sleeves 91 and 93 positioned adjacent to the valves come into contact with bends 90b and 92b of the valves 90 and 92. Contact surfaces 91a and 93a of the sleeves 91 and 93 are formed into wave shapes across the whole circumference.