A filament winding device comprising: a liner supporter which supports a liner to be rotatable about an axis of the liner; and a helical winding unit which includes fiber bundle guides that are aligned in a circumferential direction of the liner and guide fiber bundles to the liner, the filament winding device helical-winding the fiber bundles supplied through the fiber bundle guides onto the rotating liner by moving the liner supporter and the helical winding unit relative to each other in an axial direction of the liner, the filament winding device further comprising a fiber bundle retainer which is configured to temporarily retain the fiber bundles at least when the liner is replaced, and the fiber bundle retainer including: a reel member which includes an outer peripheral portion having pins that are movable in the axial direction relative to the fiber bundles supplied through the fiber bundle guides and are rotatable about the axis of the liner, the reel member being capable of winding the fiber bundles onto the outer peripheral portion; a first cutting unit which is configured to cut a part of each of the fiber bundles in the circumferential direction, the part being between a part of the fiber bundle wound on the outer peripheral portion and a part of the fiber bundle wound on the liner; and a second cutting unit which is different from the first cutting unit and is configured to cut a part of each of the fiber bundles in the axial direction, the part being wound on the outer peripheral portion. a liner supporter which supports a liner to be rotatable about an axis of the liner; and a helical winding unit which includes fiber bundle guides that are aligned in a circumferential direction of the liner and guide fiber bundles to the liner, the filament winding device helical-winding the fiber bundles supplied through the fiber bundle guides onto the rotating liner by moving the liner supporter and the helical winding unit relative to each other in an axial direction of the liner, the filament winding device further comprising a fiber bundle retainer which is configured to temporarily retain the fiber bundles at least when the liner is replaced, and the fiber bundle retainer including: a reel member which includes an outer peripheral portion having pins that are movable in the axial direction relative to the fiber bundles supplied through the fiber bundle guides and are rotatable about the axis of the liner, the reel member being capable of winding the fiber bundles onto the outer peripheral portion; a first cutting unit which is configured to cut a part of each of the fiber bundles in the circumferential direction, the part being between a part of the fiber bundle wound on the outer peripheral portion and a part of the fiber bundle wound on the liner; and a second cutting unit which is different from the first cutting unit and is configured to cut a part of each of the fiber bundles in the axial direction, the part being wound on the outer peripheral portion. a reel member which includes an outer peripheral portion having pins that are movable in the axial direction relative to the fiber bundles supplied through the fiber bundle guides and are rotatable about the axis of the liner, the reel member being capable of winding the fiber bundles onto the outer peripheral portion; a first cutting unit which is configured to cut a part of each of the fiber bundles in the circumferential direction, the part being between a part of the fiber bundle wound on the outer peripheral portion and a part of the fiber bundle wound on the liner; and a second cutting unit which is different from the first cutting unit and is configured to cut a part of each of the fiber bundles in the axial direction, the part being wound on the outer peripheral portion.