The sea dikes is often constructed on silty soft ground and faces complicated environmental conditions such as tidal current and bad weather,and it is difficult to determine the deformation control standard of the sea dike project.Based on the measured data of the large sandbag embankment in Hengsha Island,we study the deformation control standard of the embankment from three indices,i.e.,the settlement rate,horizontal displacement rate,and ratio of settlement rate in the channel to horizontal displacement rate at the slope foot.The results show that the boundary effect is obvious during the surcharge period of the embankment,and it is limited to take the settlement rate as the main criterion of the stability of the large sandbag embankment.Since the horizontal displacement rate at the shallow strata is possibly beyond the standard value due to the compaction effect,it shall not be used to control the initial construction of embankment.The validity of the critical state line based on the ratio of the settlement rate in the channel to the horizontal displacement rate at the slope foot to control the stability of the large sandbag embankment is verified,and corresponding suggestions are put forward.