The coastal waters of the North of Vietnam, strongly influenced by human impacts such as seaports, industry, agriculture and tourism services, these activities have released many pollutants into the environment such as: grease, heavy metals…, they adversely affect marine ecosystems such as corals, mangroves, estuaries, bays. Therefore, it is necessary to monitor and evaluate the quality of the sedimentary environment in the area periodically and regularly to serve the planning, use and management of exploitation of marine environmental resources in general and sedimentary environment in particular. Sediment quality in 2021 at monitoring stations ranges from good to very good, of which Bach Long Vi station achieves very good quality (SQI = 100). Compared to 2019 and 2020, the quality of sediments 2021 reached the best level. The coastal waters of northern Vietnam have had a positive change in sediment quality (Due to the impact of the Covid-19 epidemic, production, tourism, and shipping activities are limited, so the amount of waste discharged into the marine environment in the area has decreased).