This research uses a nonlinear finite element analysis to evaluate and validate two experimental specimens. The Hognestad stress-strain model is used to express the uniaxial compressive behavior of concrete to define three-dimensional concrete in the ABAQUS software, and the linear model is utilized to introduce its tensile behavior. Furthermore, a bilinear model with kinematic hardening is used to simulate the behavior of the steel. Both corner and knee joints, including transverse beams and slabs, are investigated using experimental results from different aspects, including force-displacement hysteresis diagram, the effect of stiffness deterioration, fractural mode, energy absorption rate, and the contour of fracture, and von Mises stress. This study examines two different models which present the predictive modeling, so it is shown that the current model has remarkable power and high reliability by taking into account some important effective parameters in the modeling, such as vulnerable regions, design codes defects, the impact of concrete confinement in large plastic strains, and local buckling. To sum up, this research not only provides a reliable model with the lowest inaccuracy in the study of concrete corner beam-column under seismic load but also presents a simplification in the modeling process that highly reduces analysis time.