Research conclusions: According to the characteristics of disposal engineering of the foundation of the blowing sand reclaimation，a 3 － D numerical model was established to study the settlement caused by the dynamic compaction． Its results was compared with the data of some actual projects for treating the sand － soil with the dynamic compaction method． By loading with compaction hammer，the volume of void was decreased and the density of the soil was increased，obtaining good treatment result． This method was available for treating the foundation of blowing sand reclaimation in the coastal area． The most reasonable dynamic compaction parameters were got by comparing and analyzing the numerical simulation research and the actual project，and it could provide the reference to the similar works．