Recently, the frequency of earthquakes has been increasing worldwide. As a result, steel reinforced with seismic performance that can satisfy the social needs to strengthen the existing seismic performance of existing infrastructure facilities and new buildings has become important. In general, to secure the yield strength of reinforcing bars and to reduce the production cost, reinforcing bars are produced by rolling the surface through a facility such as a Tempcore. In Korea, most of them have adopted the Tempcore process to ensure the mechanical requirements of the product. However, the use of a small amount of alloying elements and the application of Tempcore have limitations in producing reinforcing bars that require seismic performance. In recent years, remarkable progress has been made in the production and application of high strength rebars. Microalloying and fine-grain strengthening are the most effective methods in developing high strength rebars. That is, the precipitation of V (C, N) is promoted by the addition of V to improve the strength by precipitation strengthening of V-carbonitride. However, in V-microalloyed reinforcing bars, it was confirmed that the required strength did not increase proportional to the amount of V added. In this study, the effects of vanadium and other alloying elements on the mechanical properties and yield ratio of steel bars were investigated by tensile test results and microstructural evaluation.