Abstract: The lithology of the South Yellow Sea Basin is medium-dense gray silt, the sand particles are evenly graded, and the pore water is saturated, commonly known as the iron plate sand stratum. When the jack-up drilling platform is inserted into the stratum, the pile legs are difficult to enter the mud, and the depth of entering mud is small. In addition, with the change of the platform and the environmental load, the pile legs will sink, which seriously affects the safety of the operation and the platform. Through the analysis of reasons for the shallow depth of pile insertion and the subsidence of pile legs during the operation of an exploration well in the iron plate sand stratum of the South Yellow Sea, the measures and suggestions are proposed to provide references for the subsequent similar well operations.