A filament winding apparatus efficiently performs a helical winding process in which the winding angle of the fiber bundle differs. A helical winding head includes two guide rings, adjacently arranged along an axis center of the mandrel, and guide tubes arranged at equal intervals along a circumferential direction of the guide rings. The guide rings are switchable between a first state in which phase positions of the guide tubes are matched and a second state in which the phase positions of the guide tubes are evenly shifted in the circumferential direction by a phase switching structure. Tube exits of the guide tubes are arranged close in the first state.