he offshore gold deposit in the north of Sanshan island in Laizhou city is the first offshore rock gold deposit in the world. By tracing the Sanshan island fault which extends to the sea area, it delineates the gold prospecting target area. Large gold deposits in sea area have been found by using high precision magnetic survey and shallow formation profile survey. Based on the gold prospecting survey in Sanshan island sea area, this set of gold prospecting methods and offshore drilling platform can provide guidance and reference for the future exploration of gold and other mineral resources related to faults in sea area.