The follow-up engineering construction of riprap protection for 500 kV Hainan interconnector project has some characteristics, such as great difficulty in construction, high degree automation in construction equipment, widely involving in technology field. This paper introduced the present situation investigation, the design argument, the experimental research of submarine cable in the early period of the project, as well as the preparation of rock material and the control management in the construction process of the project. The rockfall pipe technology and remote operated vehicles adopted in the project both represent the advanced development level of ocean engineering technology in the world, which has the reference significance to the development of ocean engineering technology and the research of engineering measurement equipment in China.