Abstract: A prefabricated house including: a steel-frame foundation where H-shaped steels are connected in a rectangular contour, a vertical frame and a horizontal frame composed of an H-shaped steel are arranged inside the connected H-shaped steels, and inclined frames are mounted at four corners of the rectangular contour; a seismic isolation rubber supporting the steel-frame foundation on a foundation of the prefabricated house via a supporting frame; a rectangular floor member; outer wall members erected from four peripheries of the floor member; an inner wall member mounted at a position partitioning the floor member; and a roof member with a mountain-shaped section mounted on the outer wall members via a climbing beam, wherein changing positions of a window and a door and changing a room layout can is possible by changing positions of the wall member panels or reversing outer and inner faces or upper and lower sides of these panels.