By studying the status of marine monitoring technology and understanding the disparity of domestic and foreign monitoring technology, this paper points out that deficiencies are mainly reflected in monitoring capacity, monitoring equipment and monitoring technology. In order to gain a foothold in marine monitoring, we must have our own new technology. At present, online real-time monitoring technology for heavy metal pollutants, organic pollutants, contaminants and petroleum pollutants with nutritional characteristics is the most lacking technique. A breakthrough in this area will bring a large technological change for marine monitoring, and change the extremely difficult situation of market monopoly by foreign technology.