In reinforced concrete structures, the beam-column joints are the key elements in determining structural behavior against various loads. A quick look at damage caused by past earthquakes indicates that in most cases the destruction of reinforced concrete structures is due to shortcoming in the joint zone while the other structural components have suffered little or no damage. This research is timely because a large number of reinforced beam-column joints with insufficient strength or deformation capacity are in use today in seismic regions, placing many structures and people at risk in the event of a major earthquake. Considering this fact, the need for more accurate assessment of the structural capacity of concrete components in seismic retrofit projects is felt. But to date, behavior evaluation criteria for some of structural components such as reinforced concrete beam-column joints is still based on engineering judgments and no coherent and comprehensive analytical and experimental data exist. The need to do research in this field seems to be proper and is seriously required. In this thesis, the main purpose is the review and evaluation of nonlinear behavior of interior reinforced concrete beam-column joints in order to more accurately assessing its structural capacity and also providing an analytical model to simulate joint response and its impact on overall structural behavior. For this purpose three basic experimental specimens A-M-Z-4, B01 and D07 tested by different researchers have been selected and then by changing shear demand of the joints ten new analytical specimens were defined. The modeling of joints using ANSYS software is described and to evaluate the accuracy of nonlinear analysis results, they are compared with experimental results, showing good agreement. The impact of behavior and stiffness of joint panel on overall response of basic joints are also studied. To evaluate the performance of these joints, the impact of various parameters such as column axial load ratio, joint shear demand ratio and transverse reinforcement details are investigated and in each case the relevant are presented. The moment-rotation curves obtained from finite element analysis of joints studied in specific groups are In the last part of this thesis, a practical analytical model that is applicable in common commercial softwares to simulate the elastic and inelastic behavior of reinforced concrete beam-column joints is presented.