This paper is attempted to solve the problem of contradiction of building energy efficiency with indoor air quality.Quadrangle has the character of improving indoor air quality,since it always refreshes air intelligently.The courtyard has a long air column covering over the courtyard and the insulation of such a thick air layer can resist heat loss.As oxygen from outer space enters the courtyard,the energy can be recovered by oxygen.So,the contradiction of building energy efficiency with indoor air quality can be solved.The indoor air quality can be improved by the quadrangle combined with solar houses.