HOV Shenhaiyongshi，a 4500m-class manned submersible, is developed with the support by the National High Technology Research and Development Program (“863”program) during the “12th Five-Year Plan” period (2011-2015) and the National Key Research and Development Program of China during “13th Five-year Plan” period (2016-2020), whose localization rate reached 95 percent. Upon completion of its sea-trial in October 2017, it is delivered to the Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences for operation and maintainance since November 2017.