Real estate finance includes rural real estate finance and urban real estate finance. Rural real estate finance is also called farmland finance, but it has been omitted in the circle of real estate finance for a very long time. Farmland finance maybe not a problem for developed countries, but it is a key problem for developing countries, especially the socialist developing countries such as China. By means of modeling analysis, the former academic studies in the field of farmland finance are reviewed. At the same time, through the study on the generation mechanism of farmland financial institution, the recursive solution matrix of compatible motivation and critical point are obtained. Based on the foundation, the origin of the force is analyzed.