Earthquakes are considered one of the most deadly natural hazards to mankind, causing the death of thousands each year. This research aimed at gaining some insight into the real behaviour of reinforced concrete and frame structure under seismic excitation. The model of the reinforced concrete-steel frame structure was analyzed using the SAP 2000 software package. The P-Delta analysis is performed by subjecting the building to the pattern of loads increment representing the inertia forces which will be experienced by the building. As the magnitude of the load was increased gradually, the response of the building to the monotonically increasing load was observed at different points. The displacements observed were about 0.35m from joints on the first floor. The capacity curve obtained from static analysis of the building met the request curve near the elastic range at a displacement of 0.35m; this shows that the structure has good resistance to a spectrum acceleration of 0.11g which is equivalent to an earthquake of magnitude 5.2 (MW).