Dynamic loading acting on structural systems may result fromrnseveral sources such as wind and vehicular motions, etc. Therntype of dynamic input, which is of greatest importance to thernstructural engineer undoubtedly is the one that is induced byrnearthquakes.rnBuildings constructed in Seismic Zones are subjected tornearthquake ground motion in addition to other types of loads. Ifrnone tries to generate response spectrum curves of a structure forrndifferent recorded ground motions, large variations will bernobseIVed in both the response spectral values and the shape ofrnthe spectrum curves. These variations depend on many factors,rnsuch as magnitude, source, and variation in geological formationrnalong the path, local site condition and the nature of the building.rnThe recent trend of increasing height and scale of buildingrnstructures accelerated the research and investigation activities inrnthe area of Earthquake Engineering, with the aim to get rationalrnand safe earthquake resistant design criteria. Consequently, onernnrnof the current problems in evaluating earthquake response of arnbuilding is how 1D find out period of vibration of a building.rnRecent developments in the techniques for measuring period ofrnvibration of building have permitted us 1D obtain importantrnexperimental information reganling the dynamic behavior of arnbuilding during earthquakes.rnThe fundamental period of buildings can be obtained by one ofrnthe following methods: -rn1) Microtremor measurements: here ambient buildingrnvibrations are measured by using microtremors.rnThese ambient VIbrations called microtremors operaternat a very low strain level. Properly interpreted,rnmicrotremors give the fundamental period of vibrationrnof the building.rn2) Code Method -or-Equivalent Static Analysis: this givesrnan approximate formula that can be used to determinernthe first mode period of a building.rn3) Dynamic Analysis: is a sophisticated level of analysisrnavailable for finding period of vibration of buildings,rnthat employs Dynamic Time-History Analysis orrnResponse Spectral Analysis.rnIIIrnThe comparison of experimental results with the results obtainedrnby empirical formulas and dynaJnic analysis will facilitate thernengineers' understanding of the an a lysis and design of buildingrnstructures subject to dyn amic loading.rnIn the "Introduction", the background and the purpose of thisrnstudy are described. In the second chapter Period of vibration ofrnselected buildings are determined by u s ing Microtremor. In thernthird chapter Period of vibration of buildings a re determined byrnusing the Code Method. In the fourth ch apter periods ofrnbuildings are determined by using Dynamic Analysis. In the fifthrnchapter Comparison of results obtained by Microtremor, CodeMethodrnand Dynamic Analysis are done. In the last chapter,rnConclusion was made ba sed on the results obtained.