The concept and significance of updating element library of structural analysis program system were given in this paper. The refined 4-node and 8-node plane isoparametric elements in AP-1 program system were replaced with associated refined ones, and the relative compu-tational results for some standard examples were given and compared with those of old ele-ments as well as those of some other program systems.It was shown that the analysis accu-racy and computdtional efficiency of a program system can significantly be improved by up-dating element libraly,which will make the program system more competitive.