The phenomenon of impact between the adjacent buildings is one of the most important reasons for collapse of buildings during the earthquakes for that most of the codes resort to avoid impact by increasing the distance between adjacent buildings, but on the other hand high cost of land requires us to take advantage of the largest possible area in addition to the difficulty of making the separation architecturally and in particularly for high buildings the separation may offer up to 50 cm. We tried to have this research one of the studies that discuss the subject of seismic pounding where we discussed the methods for modeling the pounding and the most appropriate way to study the impact depending on the program dynamic analysis Ansys (Autodyn Ver. 11) then chose several cases for study seismic impact in three-dimensional models to cover most of the study variables that may affect this phenomenon, and we doer non- linear dynamic analysis for all cases, with applying acceleration function is defined by equation its constants are changing with processing the seismic records data. After finishing the analysis for all the models we have discussed changing the transitions and stresses and strains , and studied the factors affecting the impact , and discussed results of study and then we have summarizes the recommendations in that we see fit through this search.