Abstarct: Considering the damages and ‎injuries caused by earthquakes in ‎high-risk earthquake zones, the need ‎to design earthquake-resistant ‎structures seems undeniable. To design ‎an earthquake-proof building, it is ‎necessary to have comprehensive ‎knowledge about its response against ‎the forces caused by the earthquake. It ‎should be noted that compliance with ‎the code-specified rules and ‎regulations does not guarantee the full ‎resistance of buildings to earthquake ‎forces. Therefore, the response ‎of structures should be considered ‎carefully. This requires an exact ‎explanation of the concepts related to ‎the seismology of strong-motion ‎records and the engineering design ‎criteria With increasing population growth and limited urban land, especially in commercial and ‎industrial areas, the use of multi-story buildings is essential. Due to the limitations of urban ‎landscapes and the application of some structures, the design conditions require that the distance ‎between the columns be more than the normal value. Therefore, the use of appropriate and ‎efficient structural systems, both technically and economically, seems necessary. In these cases, ‎there are various options for designing the load-bearing system of the building. One of the most ‎effective and widely used options is to use a frxame with special truss beams. ‎ In this research, truss arrangement, cross section of truss members, ‎truss height and length of special zone of the truss moment resisting ‎frxame are optimized using genetic andisland genetic algorithm‎. The optimization code is written in Matlab ‎software environment and OpenSees software is used for structural ‎analysis. ‎ In this Thesis, the optimal design of a special moment resisting frxame ‎is performed, once under a single-‎objective, objective function with the aim of minimizing the weight and ‎again under a multi-objective, objective function with the aim of ‎minimizing weight and maximizing behavior coefficient ‎simultaneously. ‎ In this study, the coefficient of behavior is obtained from nonlinear static and nonlinear dynamic analysis and the optimal design of members is done using the rules of AISC341-16. The results showed that the island genetic algorithm has a significant convergence rate in achieving the minimum point. It is noteworthy that the evaluation of the results showed the efficiency and performance of the two-objective objective function method.Also, the comparison of the methods showed that the MPA method is suitable for structures with a ratio of total height to span greater than one And for ratios smaller than one, the NSP method also performs well. Finally, a formula for calculating the optimal truss height and the optimal specific segment length was proposed and presented.