A display device includes a plate member, an outer frame, and a display panel. The plate member has a fringe portion and a joining structure formed on the fringe portion. The fringe portion has an edge and two opposite surfaces. The outer frame has a parallel frame portion and a non-parallel frame portion extending from the parallel frame portion. The parallel frame portion is parallel to the fringe portion and is embedded into the joining structure, so as to make the outer frame and the plate member jointly from an accommodating space for accommodating the display panel. The parallel frame portion is coplanar with one of the surfaces. Therein, the joining structure can include an opening structure passing through the two surfaces and extending to the edge. Or, the joining structure can include an opening structure, passing through the two surfaces, and a raised portion.