The present invention discloses a lamp casing structure that can be assembled and installed easily and applicable for different installation methods. The lamp casing structure comprises a plurality of frame strips coupled to one another and disposed around a first transparent cover, a plurality of fasteners disposed at each frame strip and inserted into latch portions of the frame strip and the first transparent cover respectively, so that the lamp casing structure can be assembled and installed simply by a latching step, and the lamp casing structure can be installed on a wall or a ceiling, or embedded into grids of a light steel frame.