Abstract: The present invention is directed to a unitary bathroom which includes an upper back panel, a lower back panel, a base, and side panels all of which are formed by aluminum honeycomb composite boards or paper honeycomb composite boards. The invention also relate to connection among above the upper back panel, lower back panel, base, side panels and ceiling. The unitary bathroom constructed according to the invention is reliable, and structurally stable. The bathroom will not be loosened after long term use. In addition, the unitary bathroom made of aluminum honeycomb composite board is lightweight, strong, and has good stiffness. The coating material may be freely selected from ceramic, artificial stone, natural stone, aluminum alloy, stainless steel, zinc coated steel plate, fire proof plate, SMC and plastic. Moreover, it has strong shock proof ability and high fire proof ability. No deformation and aging will occur after long term use.