China's fishery has undergone the structural changes of shifting from fishing-dominated to aquaculturedominated sectors. Structural changes of mariculture sector are undergoing as a result of internal and external factors, rising demand, government promotion policies, technological advancement, resource and environmental constraints should be responsible for the evolution of geographical distribution, varieties, waters and modes, which in turn have exerted environmental impacts. It is shown that mariculture is transferring from traditional waters to deep-sea and onshore waters. Accompanying the development of new varieties, intensive modes are developed fast while traditional extensive modes are still dominant. The rapid development of intensive mariculture and modern mariculture modes has exerted internal source pollution to marine environment. To facilitate sustainable development of mariculture, it is necessary to expand the mariculture space, optimize the cultivated modes and varieties. It is believed that irrational human economic activities should be responsible for coastal water pollution and ecological degradation. Scientific guidance on mariculture industry layout, modern ecological farming pattern and reasonable matching cultured population, the development of mariculture technologies and pollution treatment facilities, and supervision and guidance of laws and regulations are urgently required to facilitate balanced sustainable development of mariculture.