Abstract: Self-established ports were these international trading ports that were opened by modern China independently, in the promotion of which the transformation of agriculture played an important role. Among them, agricultural production had been transformed from subsistence production to commodity production, thus accumulating a considerable number of agricultural products, which provided the adequate trade goods for the self-established trading ports. The concept of the priority of agriculture had been extended from emphasis on agriculture to that on commerce, actively advocating independent trades with foreign nations, which provided the ideological support for self-established trading ports. Moreover, due to the sharp decline of agricultural tax in proportion of fiscal revenue, tariff was highlighted as an important source of government revenue, promoting the impoverished government of late Qing Dynasty to open commercial ports in order to protect national financial resources, which laid a solid policy foundation for the self-established trading ports.