Buildings are affected severely during the earthquake. While design the any building in seismic zone, earthquake load are to be considered. To know the behavior of structures under seismic load there are three methods namely push over analysis, Time history analysis and Response Spectrum analysis. Based on the required result the type of method is performed. In this research the push over analysis is chosen and capacity spectrum method techniques is implemented. The Capacity Spectrum Method[CSM] is a performance based seismic design techniques and it is obtained by non-linear force - displacement curve know as push over analysis. It is widely accepted displacement based seismic design by means of graphical procedure, comparing the structure capacity with respect to ground motion of the structure. The roof displacement and base shear forces are converted to equivalent spectral acceleration and spectral displacement with respect to coefficient that shows the effective model masses and model participation factor. This spectral values defines the capacity spectrum of both structure. This paper present the seismic evaluation of RCC and Composite frame structure with irregular plan.Analysis and connection design of sixteen storied framed structure is be done by using non-liner static pushover analysis in ETABS Software. © IAEME Publication.