Legal regime of the territorial sea is analyzed from the perspectives of both of international and domestic law. The article is considering the development of the legislation regulating the Legal regime of the territorial sea in China. Author used abstract-logical, comparative-legal, formal-legal and historical methods. The article highlights the stages in the development of legislation, their peculiarities, as well as the main tasks at these stages. The main attention is paid to the Law of the People’s Republic of China on the Territorial Sea and the Contiguous Zone (1992), the conditions in which it was enacted, and its subsequent adjustments. The author examines legislation and practice of the People’s Republic of China on the following problems of the territorial sea: limits of the territorial sea, the innocent passage of foreign ships through the territorial sea, marine scientific research, protection of the marine environment in the territorial sea. The general conclusion is that the Legislation China practically comply with the 1982 UN Convention on the Law of the Sea and operates on the basis of its implementation into national legislation. Chinese law and practice as a whole is also consistent with existing customary norms of international law and take into account the prevailing trends seen in the legislative practice of a significant number of coastal states.