A cylindrical winding body is formed by winding continuous fibers impregnated with a first thermosetting resin in a circumferential direction, and the first thermosetting resin in the winding body is thermally cured. A pair of dome members is joined to both end portions of the cylinder member. A fiber bundle impregnated with a second thermosetting resin is helically wound around the joined member over the dome members, and the second thermosetting resin in the wound fiber bundle is thermally cured. A thermosetting resin containing a main agent and a granular solid curing agent is used as the first thermosetting resin, the main agent including a resin precursor and the solid curing agent chemically bonding molecules of the resin precursor together.