The utility model relates to window technology field, concretely is window frame structure, including frame, window and glass, the glass is fixed between frame and window, forms fixed window, still include sash frame, the glass is fixed in sash frame, forms sash, the sash frame with frame, window all form observation window between, be equipped with leveling portion on the sash frame, leveling portion is located observation window one side, through leveling portion can adjust the angle between sash frame and frame or window, the sash frame includes left sash frame and right sash frame, left sash frame is fixedly connected with window, right sash frame is fixedly connected with right frame, the utility model discloses through setting up observation window, whether all the observation pole end plate is pasted on frame and is gone up the edge strip, right sash frame and right frame, window and left sash frame whether installation flush are judged, after installation flush, the cavity between two adjacent is blocked by heat insulation strip, avoid producing heat
convection, improve the heat preservation and heat insulation performance of window.