The invention discloses a purification area double-glass magnesium-rock-wool-color-plate room and a construction method thereof, and relates to the field of building construction. The purification area double-glass magnesium-rock-wool-color-plate room includes a civil ground and a civil wall built on the civil ground, and further comprises a color steel wall plate and color steel ceiling plates; the color steel wall plate includes wall-mounted color steel wall plates which are connected to the inner wall of the civil wall in an attached mode and a separation color steel wall plate installed between the wall-mounted color steel wall plates; and the color steel ceiling plates are arranged between the top surfaces of the wall-mounted color steel wall plate. U-shaped fasteners are arranged atthe connection joints between the facades of the adjacent two color steel ceiling plates and the butt joint facades of the adjacent two color steel ceiling plates in a fastened mode. The facades of the U-shaped fasteners are fixed in a clamped-connection mode through bearing-inserting connecting pieces; the bearing-inserting connecting pieces are each of a hollow strip structure, and include inserting block parts with interior being rectangular and hollow and a pair of clamping edge parts arranged on the middle parts of one opposite sides of the inserting block parts. The problems that an existing color plate room is inconvenient to install, color plates cannot be disassembled, and the flatness and comfort are low are solved.