Abstarct: After significant damage of Northridge earthquake to steel bending frxame connections, the researchers sought to improve the behavior of the bending frxame by making suitable connections. So many studies have done and the connection has suggested that the slotted connection is one of them that by removing the shear force in the beam web and the transfer of plastic joint into the beam and away from the connection causes improvement of the connection. The selection of suitable geometry requires many expriments and modeling, which will need lots of cost and time for modeling and experiments. In this study, it is intended to find the most optimal model of a slotted connection with the RSM and compare its behavior with the slotted connection. The purposed model optimization is used powerful method to improve the strength and flexibility of the structure, increase the energy absorption of the slotted model compared to the initial slot length and prevent structural damage by decreasing stress and strain transfer from beam to column. According to the obtained results, the RSM method has been capable of providing more resistance, ductility, and energy absorption than the initial specimen and the use of this method also decrease the stress and strain at the beam to column area and the panel zone and Reducing computational cost the conclusion process.