A method for manufacturing a catheter includes a process of supplying a resin material in a melted state to the periphery of a core wire (90) and molding a hollow tube (82) having the core wire (90) inserted thereinto a process of arranging the hollow tube (82) having the core wire (90) inserted thereinto, on an outer peripheral side of a main lumen forming region of a tubular body part (10) made of resin a process of extracting the core wire (90) from the inside of the hollow tube (82) to form a sublumen after the core wire (90) inside the hollow tube (82) is elongated and reduced in diameter to peel off the hollow tube (82) and the core wire (90), and a process of inserting an operating wire into the hollow tube (82).