The object of research is a connection of precast reinforced concrete frame elements made using composite rods. This work aims to numerically study the stress-strain state of prefabricated reinforced concrete frame elements' connections. Method. A flat finite element model is used to analyze the stress-strain state of the precast concrete element's connection. The physically nonlinear finite elements are used for concrete modeling. A nonlinear stress-strain diagram for concrete was applied for calculations, given in the regulatory documents for the reinforced concrete structures design. The deformation diagram of steel reinforcement is elastic plastic. Composite rods are deforming elastically. The polyurethane sheets were modeled by nonlinear two-node finite elements working in compression. Results. A numerical analysis of the stress-strain state of a prefabricated frame with the proposed connections of a beam and a column under the action of two loading options has been performed. The results of calculations of prefabricated and monolithic reinforced concrete frames are compared. The comparison results show that the proposed joint connection between the beam and the column provides the required strength and rigidity of the frame.