Dual structural systems are still efficiently used by civil and structural engineers to addressrnthe public demand for residential buildings, schools, hospitals and office buildings.rnFurthermore, they are effective in resisting lateral loads by combining the advantages of theirrnconstituents. However, dual structural systems with moment frames are designed to carryrnlateral forces in longitudinal direction entirely while structural walls are positioned in shorterrnside of the building to resist transversal lateral loads are challenged by Northridgernearthquake. After then, this type of dual system is cited by Erdy Charles k. (2007) asrndangerous combination of shear walls and moment resisting frames. Hence, in an effort tornaddress this problem, comparative analysis among the sample dual system buildings withrndifferent shear walls arrangement is carried out and overall seismic performance of the dualrnsystem is evaluated using non-linear push over analysis method. Three cases of shear wallrnarrangements for each sample building are used to examine the effect of different shear wallsrnarrangement on the whole system, their interaction with frames and their out-of-planernbending resistance. Results of non-linear push over analysis are obtained for each case in thernform of capacity curves and plastic hinge formation patterns. The observation of these resultsrnshows that the overall seismic resistance capacity is dependent on the shear wall location.rnAlso it reveals that the shear walls are vulnerable to local failure due to bending moment inrntheir out-of- plane direction, regardless of their location. Therefore, caution should have to berntaken during designing of this type of dual system in order to avoid premature collapse ofrnshear wall in its out-of-plane direction, which may perhaps leave the building defence less torntransversal components of earth quake load.