Abstract: The marine clay in Houhai Bay of Shenzhen has several special properties including high water content, large void ratio, high compressibility, low strength and under-consolidation. It is found that the measured settlement rate is greater than the theoretical one during loading, and it is opposite at full loading stage by analyzing the monitoring data of Shenzhen-Hongkong West Corridor offshore filling and soft soil treatment project. According to theoretical results, the curve should be close to straight line after 120 days, and the settlement rate will be less than 1 mm/d. Actually, the field settlement rate changes very slowly and tends to be stable after 240 days. The measured consolidation time is one time greater than the computed one when consolidation is finished because of the decrease of primary consolidation coefficient of the marine clay in Houhai Bay of Shenzhen with the increase of loading. The experimental results show that the consolidation coefficient decreases by 2×10^-4 cm²/s when the effective loading increases by 100 kPa. The theoretical curves corrected by consolidation coefficient basically fit well with the field ones, and it is proved that the proposed consolidation laws are right. It may provide references for the design and construction of similar projects.