The surface subsidence is a direct index indicating in unloading time,and the calculation accuracy has become one of the difficulties faced by all kinds of engineers.To study the dynamic change of reinforcement effect with a soft foundation construction process,the measured data of surface subsidence has been converted to the same interval by hermite interpolation in this paper.Base on the conversion results,GM(1,1)model and the corresponding function with time has been established to predict the surface settlement in different time.The results of analysis showed that the calculation accuracy by the GM（1,1）prediction model is the first level,which could well predict the surface subsidence in different time,meanwhile,it would provide reference and guidance for solving the related complex settlement prediction problems in the future.