Due to the durability of steel structure，there are few design cases of inserted steel cylinder structures in China. Based on the third runway reclamation project of Hong Kong Airport，we propose a design scheme of using the inserted steel cylinder as the temporary enclosure structure for land on the deep soft ground，apply the two-dimensional calculation theory of OCDI for the structural design，and use the software of PLAXIS 3D to recheck the structural displacement and overall stability. The results show that the OCDI two-dimensional theory for structural design is safe，but the displacement calculation results are seriously small. The achievement can provide references for the similar projects.