According to the curtain wall industry development planning and design current state, a variety of mechanical models was analyzed; authors advise that the multi－span articulated beam mechanical model should be chosen as far as possible design of vertical column structure according to the reality situation; the mechanical model of the multi－span hinged beam should be selected as main method during the calculation, the proportion of the cantilevered beam and the simply supported beam should be adjusted, which could make wall engineering achieve the better economic benefit.