Present days, the high rise building structures developed in worldwide. The major problems in tall building structure design to resist during the great vibrational effect of earthquake and wind load. The behavior of tall structure under the action oflateral load goes to laterally movements; to insure these structures against lateral load the two major techniques are generally adopted. One is the especially arrangement are made in ordinary framed R.C. building are helps the easily resisting lateral load by arranged member and the gravity load carry by base framed structure which specially arrangement are called structural form. Present study based on the significant of diagrid structural system over the framed building. For finding optimal angle of diagonal several models of 20, 42 and 60 storey diagrid building having different diagonal angles i.e. 320, 510, 620, 680, 750, 820 and 900 are created and analyzed by equivalent static method and Response Spectrum method and results have been compared in terms of maximum lateral displacement, angle at which displacement minimum is called optimal angle.Optimum angle range for 20 storey diagrid building is 50 degree to 65 degree and for 42 storey and 60 storey diagrid buildingis 62 degree to 75 degree and it is observed that total steel usage in diagrid buildings are also less than steel usage in conventional buildings.Keywords: Trusses, hot rolled steel, cold forged steel, Howe truss, Pratt truss, Warren truss