Building public rental house is aiming at solving the problem of housing safeguard of low-income people. The level of whole cycle rent cost can influence tenants rent choice. This article uses the theoretical analysis method, discusses the factors that influence the whole cycle cost, and constructs the whole cycle cost model, and analyzes the influence of transportation cost, rent period, rent level and other factors. And it takes Chongqing as an example, invests the whole cycle tenant rental cost, combines with the relevant policies and practice in Chongqing, and puts forward suggestions on rent cost problems.