Investment has a far and fixed influence to the development of society and economy. China is a big agricultural developing country, and its capital will be hard up for a long time. It is urgent affair to add agricultural investment in reason, to advance the agricultural synthesis throughput and benefit, and to buildup the stamina of agriculture. The reform and innovation of agricultural investing and financing system, is an important base and precondition to accomplish the stratagem adjustment of agriculture, under the condition of market-economy.In this dissertation, we merged agricultural financing into agricultural investing by the first time, used the standpoint of institution economy, put the changing of agricultural investing and financing into the background of history, reality and future, especially the expanse field of vision of joining WTO. Firstly, we historically and systematic evaluated the changing of agricultural investing and financing system, since the beginning of the foundation of China. We divided the whole history of agricultural investing and financing system into three periods, those are forming and waving period (1953-1978), reforming and standing period (1978-1992), innovating and consummating period(1992~up to date). With the view of institution economy, we analyzed the moving patterns and its characteristics of different periods, appraised the system's efficiency. We can see that, the force that brought about the system changing is coming from the pressure of society system. Because of the plan-economy system base and strategic position of Chinese agriculture, the changing of the system is involved into the range of society system reform, so the changing shows the feature of compulsive changing.We got rid of the hedge of traditional method, and analyzed the bodies' behaviors of agricultural investing and financing by inducted game theory. The bodies lack hard constrains to adjust their respective agricultural duties, and they have investing and financing decision and equilibrium of the second and third industry. Whereas, central government and local governments, governments and farmers all lack hard laws to restrain respective behaviors. There is a soft, new sanction on the point of whether adding capital into agriculture. So every body makes its choice relying not only on its own decision, but also on the choices of others. Some relationship of compulsion and obey exist between governments and farmers, so the game between them is a cooperative game. There are fighting for financial capital, for benefit policy, for banking capital among localgovernments'. The function of central government and local government is different, while the information is not completed symmetry, so it is difficult for central and local governments to add capital in agriculture as the result of game.In the economy-market system, the rising of capital market provides the possibility of gaining large amount of capital. Take the security market as an example, we analyzed the contribution to agricultural capital by the capital market, giving a fringe explore for the future agricultural investing and financing.We chose behavior function to forecast the supply and demand of future agricultural capital through comparison. The period 2004 ~ 2009 and 2014-2019 will have the lager gap of shortage, lack about 6%, the earlier 21centure and 2026-2030 lack less than 5%.In the end, through learning the foreign experience, we pointed out the strategic choices, such as: "Perfecting agricultural investing and financing system, which is dominated by the government", "consummating the setup of financing agricultural investing and financing system of government and the setup of macro-control", "changing the functions of government, elaborating the allocation rule of market ", "improving the farmers' income, mobilizing their enthusiasm to investing agriculture".