Abstract:This paper presents the proporties of drainage system and the form of drainagesystem and analyses the drainage system of highrise residential and hotel buildings. The results of re-search show that it is suitable to adopt separate systeni when highrise residential and hotel buildingsare not more than twenty floors. It is feasible and economic to adopt the complementary wet ventdrainage system rather than the three-pipe system when the diameter of vertical drain is 100 mm.