To provide a process for manufacturing a variable flange of a continuously variable transmission which can provide good workability in spinning process and impart sufficient hardness by carburizing and quenching process.

A steel material comprising 0.15 to 0.20% by weight of carbon, 0.35 to 0.81% by weight of manganese, 0.05 to 0.15% by weight of silicon, less than 0.015% by weight of phosphorus, less than 0.02% by weight of sulfur and 0.03 to 0.2% by weight of titanium in which the balance is iron, is subjected to hot forging to form a flange material 21 comprising an axis hole 8a and a disk like body 9 provided with a flange face 9a and a preform part 22 for forming a cylinder part 10. A carburization preventive agent 23 is applied to the preform part 22. The flange material 21 is subjected to carburizing and quenching process. The carburization preventive agent 23 is removed from the flange material 21, and the preform part 22 is subjected to spinning process to form a cylinder part 10. The steel material contains 0.001 to 0.002% by weight of boron.