Restricted by economic and social development conditions and the level of domestic regulatory system construction, the traditional host country-centered regulatory approach makes it difficult to ensure “responsible investment” by overseas farmland investment companies. The jury is still out on whether international law can directly impose obligations and responsibilities on companies. Therefore, it is realistically necessary for the investor’s home country to regulate any behavior that infringes on the human rights and environment of residents of the host country during the company’s overseas farmland investment. We used a panel fixed effects model and the dummy variable method to construct regression indicators based on international treaties. This study finds that promulgating responsible investment treaties can significantly promote the scale and number of international farmland investments, which also further led to the problem of differentiation among overseas farmland investors. We further discussed the lack of binding force of current international rules and the difficulty in coordinating the interests of multiple parties. In the regulatory system of the home country, there are still problems, such as insufficient supply of adequate laws, and lack of administrative guidance. Measures such as deepening negotiations on international rules for responsible overseas farmland investment, further leveraging the role of land ownership in responsible overseas farmland investment, improving existing domestic legislation, and strengthening administrative guidance on overseas farmland investment can be used as countermeasures.