A method of manufacturing a display device includes: preparing a cover window including a bent part on a side surface thereof, and a guide film including a surface on which a display panel and an adhesive layer are arranged; arranging the cover window and the guide film in a face-to-face manner such that the adhesive layer faces the cover window; seating the guide film onto a seating pad of a first jig; pre-forming the display panel by bringing opposite ends of the guide film into close contact with opposite side surfaces of the seating pad using a pair of push members; and joining the display panel with the cover window by bringing the adhesive layer into contact with the cover window.