Abstarct: Today, the use of prestressed slabs has become widespread due to their many advantages. By applying the prestressing technique in flat slabs, it is possible to achieve structures with longer spans and less thickness than conventional flat slabs, which leads to a reduction in material consumption and weight of the structure. Post-tensioned slabs are usually designed and constructed to withstand gravity loads and the use of these systems as a lateral force resisting system in areas with high seismic risk is prohibited. However, prior experimental studies reveal that these systems have the potential for energy dissipation, which can be used as a lateral force resisting system or a system that can help the other lateral force resisting systems. In this research, conventional and prestressed slab systems along with moment frxame systems with wide beams have been used to investigate their seismic behavior. The use of wide beam moment frxame systems in seismic areas is allowed as a lateral force resisting system and also increase ceiling height. For this purpose, in order to better understand the seismic behavior of post tensioned slabs, an exterior unbonded post tension slab column connection has been validated in ABAQUS software and the effect of various parameters such as compressive strength of concrete, the amount of effective prestressing levels and the bonding influence in the seismic behavior of post tension slab joints are investigated by comparing the ultimate strength, stiffness and ductility, then a reinforced concrete (non-prestressed) slab column connection and an exterior RC wide beam column connection validation was performed, then three specimens of wide beams with different dimensions were modeled with post tension and conventional slabs and seismic parameters in this system were investigated. Also, by adding the slab and prestressing it to the wide beam moment frxame system, the effect of prestressing forces on the seismic behavior of the slab has been investigated. The results showed that increasing the compressive strength and prestressing level of concrete increases the stiffnes, ultimate strength and ductility, while the bonding condition does not have much effect on the behavior of the joints. Adding a wide beam to a conventional slab also significantly increases the ultimate strength and ductility. The stiffness of the model also increases in specimens with a wide beam thicker than the slab thickness. In specimens with post tension slab and wide beam, an increase in stiffness and strength is observed, but no significant change in ductility is observed. Also, adding slab to wide beam moment frxame systems does not have much effect on the ultimate strength but increases the stiffness and ductility and the presence of prestressing forces causes a significant increase in the ultimate strength but has little effect on ductility.