In large cities, the rental housing supply for middle income class is going to be important more and more, besides that for low income class. We have two methods to increase rental housing supply for middle income class in general-the direct method and the indirect method. The direct method means the supply of public housing by public bodies, and the indirect method means the supply of private housing promoted by public bodies. In this study, we tried to analyze the effect of the indirect method, based on the questionnaires to managers of private rental housing. As the result, we could found out that the indirect method was effective to promote rental housing supply for middle income class, but the quality of housing was various according to financing conditions.