To provide portable electronic equipment whose case is cylindrically molded by extrusion-molding, and configured to easily assemble/disassemble an internal component disposed in the case to/from the case, and to provide its assembly method.

The lens unit 20 is disposed in the case 12 through an opening 18 formed in the rear side of the case 12. As shown in Fig 2, the lens unit 20 is pressurized with the energizing force of a receiving plate member 26 of an LCD, that is insertion-disposed in the case 14 through the opening 18, to the front inner wall surface 12A of the case 12, then, the lens unit 20 is assembled. Thus, the lens unit 20 is easily assembled to the case 12, and also, the lens unit 20 is easily disassembled from the case 12 by detaching the receiving plate member 26 from the opening 18 of the case 12.