Seafloor Polymetallic Sulphides (PMS) is deep sea mineral that is confirmed to exist within Japanese exclusive economic zones and expected to develop as a new supply source for Japan. However, deep sea minerals including PMS have not been commercially developed so far, although various countries are eagerly working it. Japan Oil, Gas and Metals National Corporation (JOGMEC) has been commissioned by Ministry of Economy, Trade and Industry (METI) to conduct practical study on PMS for commercialization. As part of the efforts, JOGMEC implemented “Excavating and Ore-lifting Pilot Test” from the middle of August to end of September 2017. In the test, JOGMEC succeeded in consecutive lifting of ore and sea water in a state of solid-liquid flow from a depth of approximately 1,600m for the first time in the world. Through the test, it became clear that there are still many technical challenges left to be resolved for development of PMS such as improvement in durability of equipment, system optimization, adjustability of ore grain size and slurry concentration and so on. JOGMEC will continue efforts aimed at commercialization of PMS from a long-term perspective.