A manufacturing method for a high-pressure tank that is used to store fluid, characterized by comprising: a step of preparing a liner that has a cylindrical portion (20, 42) having a cylindrical shape and dome portions (30, 44) having a domical shape and provided on both ends of the cylindrical portion (20, 42); and a fiber reinforced plastics layer forming step of forming a fiber reinforced plastics layer on an outer surface of the liner by filament winding, wherein the fiber reinforced plastics layer forming step includes: an inner helical layer forming step of forming an inner helical layer by winding a fiber impregnated with thermosetting resin on an outer surface of at least part of each dome portion (30, 44) and an outer surface of the cylindrical portion (20, 42) by helical winding; an inner hoop layer forming step of forming an inner hoop layer by winding a fiber impregnated with thermosetting resin on an outer surface of the inner helical layer on the cylindrical portion (20, 42) by hoop winding in multiple layers; and a mixed layer forming step of forming a mixed layer by laminating an outer helical layer, which is formed by winding a fiber impregnated with thermosetting resin by helical winding, and an outer hoop layer, which is formed by winding a fiber impregnated with thermosetting resin by hoop winding, on an outer surface of the inner hoop layer and an outer surface of the inner helical layer on each dome portion (30, 44), the inner hoop layer and the outer hoop layer in the mixed layer constitute a hoop layer; characterized in that the inner helical layer forming step, the inner hoop layer forming step and the mixed layer forming step include a step of forming the inner helical layer, the inner hoop layer and the mixed layer such that, on the cylindrical portion (20, 42), 90% or more of the hoop layer in a thickness direction of the fiber reinforced plastics layer is arranged within a range in which 75% of the fiber reinforced plastics layer in the thickness direction of the fiber reinforced plastics layer is arranged, the 75% of the fiber reinforced plastics layer being adjacent to the liner. a step of preparing a liner that has a cylindrical portion (20, 42) having a cylindrical shape and dome portions (30, 44) having a domical shape and provided on both ends of the cylindrical portion (20, 42); and a fiber reinforced plastics layer forming step of forming a fiber reinforced plastics layer on an outer surface of the liner by filament winding, wherein the fiber reinforced plastics layer forming step includes: an inner helical layer forming step of forming an inner helical layer by winding a fiber impregnated with thermosetting resin on an outer surface of at least part of each dome portion (30, 44) and an outer surface of the cylindrical portion (20, 42) by helical winding; an inner hoop layer forming step of forming an inner hoop layer by winding a fiber impregnated with thermosetting resin on an outer surface of the inner helical layer on the cylindrical portion (20, 42) by hoop winding in multiple layers; and a mixed layer forming step of forming a mixed layer by laminating an outer helical layer, which is formed by winding a fiber impregnated with thermosetting resin by helical winding, and an outer hoop layer, which is formed by winding a fiber impregnated with thermosetting resin by hoop winding, on an outer surface of the inner hoop layer and an outer surface of the inner helical layer on each dome portion (30, 44), the inner hoop layer and the outer hoop layer in the mixed layer constitute a hoop layer; characterized in that an inner helical layer forming step of forming an inner helical layer by winding a fiber impregnated with thermosetting resin on an outer surface of at least part of each dome portion (30, 44) and an outer surface of the cylindrical portion (20, 42) by helical winding; an inner hoop layer forming step of forming an inner hoop layer by winding a fiber impregnated with thermosetting resin on an outer surface of the inner helical layer on the cylindrical portion (20, 42) by hoop winding in multiple layers; and a mixed layer forming step of forming a mixed layer by laminating an outer helical layer, which is formed by winding a fiber impregnated with thermosetting resin by helical winding, and an outer hoop layer, which is formed by winding a fiber impregnated with thermosetting resin by hoop winding, on an outer surface of the inner hoop layer and an outer surface of the inner helical layer on each dome portion (30, 44), the inner hoop layer and the outer hoop layer in the mixed layer constitute a hoop layer; characterized in that the inner helical layer forming step, the inner hoop layer forming step and the mixed layer forming step include a step of forming the inner helical layer, the inner hoop layer and the mixed layer such that, on the cylindrical portion (20, 42), 90% or more of the hoop layer in a thickness direction of the fiber reinforced plastics layer is arranged within a range in which 75% of the fiber reinforced plastics layer in the thickness direction of the fiber reinforced plastics layer is arranged, the 75% of the fiber reinforced plastics layer being adjacent to the liner.