To provide a curved hose forming method capable of detaching a curved hose after vulcanization from a mandrel without exerting adverse effect on the final shape of the molded hose, and the mandrel therefor.

A hose having a predetermined length is externally fitted to the mandrel having a plurality of leg parts. The mandrel has at least two leg parts and both ends of the hose are arranged on the leg parts of the mandrel and a part of the hose is not supported by the mandrel. The unsupported part of the hose may be straight or may be formed into a loop so as to form a more complicated curved hose. The unsupported part of the hose can be also held at a predetermined position by the mandrel for an outer surface.