Abstract: Underwater baseplate installation in advance is needed for semi-submersible platform pre-drilling well.However,underwater baseplate installation by drilling ship has some disadvantages as follows:long occupancy time of drilling rig,high operation cost,complicated operation process,higher requirement of sea situation and so on.According to such disadvantages as tense resource situation of drilling ship and traditional baseplate installation,by feasible demonstration of experts,the underwater baseplate is firstly installed successfully by suction pile technology,when the installing accuracy satisfies the requirements of operation completely.In a word,the suction pile type installation is an underwater baseplate installation technology in worthy of popularization,which needn’t occupy drilling rig,can save drilling time,and has lower cost than that of drilling ship installation.