Abstract: A typical masonry building of middle and elementary school was built in 1980's.In the process of re-design seismic strengthening the building, First, the seismic appraisal of the building is assessed, the results show that the stable base, the lower strength of material in the upper part, and non-reasonable structural design.Then we analyze the rationality of the structural reinforcement and determine the seismic effect coefficient.The structure calculation was run for before and after strengthening building, and the nodes of the important and complex part were re-design.