Abstract:More coastal levees are located on soft soil foundation in Guangdong Province,and the failure mechanism is related to the deformation of soft soil. The failure reason and mechanism of dikes on soft soil foundation are analyzed. In order to improve the stability of levee,the measures,such as improving foundation bearing capacity,removing wave energy,optimizing section pattern,adopting lightweight fill material,are effective for constructing dike on soft soil foundation. Based on optimized design theory and integration analytical model of levee structure and its foundation,a case study of the influence of design factors on levee stability is analyzed,including the slopes of upstream and downstream,material self-weight of pave dike,zone of foundation improvement .The optimized results show,using the section where downstream is slower than upstream is avail for overall stability of dike,and that using lightweight fill material can overcome some disadvantages of soft basement. In addition,soft soil treatment should be focused on shallow foundation under levee.