According to present value model, it adopts seasonal data of price for sale and rent in China’s 35 cities’ realty from third season 1999 to second season 2006 and finds the cointegration vector between sale price and rent which have been examined by using panel data, and suggests to take houses’ sale price and rent as an important factor for realty’s risk evaluation. Furthermore we analyze the rate of growth of price for sale and rent in different time and different cities.