A portable display device may include a display panel, a window, an attaching member and a blocking member. The display panel may have a drive circuit region and a display region. The window may be positioned facing to the display panel. The attaching member may be interposed between the display region of the display panel and the window to attach the display panel to the window. The blocking member may be arranged on a boundary line between the drive circuit region and the display region to prevent the attaching member from infiltrating into the drive circuit region. Thus, flows of the attaching member may be readily controlled using the blocking member having a simple structure to prevent the infiltration of the attaching member into the drive circuit region. As a result, the portable display device may be assembled by a simple process and a low cost.