For analysis of laterally loaded piles in clay, the p-y curve method was widely used. Most p-y curve models were based on field tests, and were considered to be more realistic. Summary of commonly used experimented p-y curve models indicated that the form of measured p-y curves was complex and actual p-y curves were hardly founded out exactly. Elastic-plastic model was a simple model, which can predicted deformation behavior and load distribution of the lateral loaded piles in clay accurately by choosing appropriate parameters. After the calculation of the examples, the elastic-plastic method was proved to be simple, definite and universal, so it could be widely used instead the complex measured p-y curves in engineering.