Abstarct: Due to losses caused by lateral loads and the results of tests conducted and the study buildings damaged by the lateral loads, the connection will be see the weakest and most vulnerable parts of structures are concrete against lateral loads such as earthquakes. It is therefore necessary to further investigate the connections in concrete structural. Hence, in this thesis to model and analyze connections in concrete structures to assess their performance and behavior in the face of gravity loads and lateral loads to be addressed. Analysis in this study baxsed on nonlinear static analysis under monotonic loads (uniform).to be reinforcement model of the connenctions has been studied for two different corners connections (L) and an external connection (T) has been formed. In this thesis, we try to make the investments in the bar connectivity, location and detailed maximum plastic strain and stress peak (which is the main reason for the failure of the connection is be) to the region the beam is moved away from the connection. For this purpose with the horizontal and vertical displacements of the joints, function, behavior, stress, strain and the reaction in connenctions and the results is given in Table and Fig. With the obtained results in the connecyions in concrete structural can change and reinforcement arrangement of the armature at theconnenctions that leads to hardening the connections and weakening of the local area connection that is supposed to hit the plastic hinge maximum strain and stress taken place, the structural damage to the plastic joints of the beam and connection failures can be prevented.