When using steel scraps containing Cr and Mn as raw materials in electric arc furnace (EAF) steelmaking, EAF steelmaking slag containing Cr₂O₃ and MnO is inevitably produced as a by-product. Since Cr and Mn are valuable elements, it is economically and environmentally important to recover by reduction of EAF slag and reuse those elements into steelmaking process as alloying materials. In this study, to improve the recovery efficiency, flux addition to EAF slag was investigated both thermodynamically and experimentally. At first, thermodynamic calculations were performed using Al₂O₃, CaF₂ and SiO₂ as candidate fluxes, and it was found that SiO₂ has the greatest potential to increase the slag liquid fraction and to improve the recovery efficiency. Then, reduction experiments using an actual EAF slag containing 8 mass% Cr₂O₃ and 6 mass% MnO were carried out at 1573 K with SiO₂ flux addition. As a result, slag liquid fraction and the recovery efficiency of Cr and Mn increased with increasing the amount of SiO₂ addition. Up to 81% of Cr and 61% of Mn in an EAF slag could be recovered. Furthermore, reduction experiments using different reducing agents were conducted. Despite the slag liquid fraction being the same, differences in recovery efficiency were observed. It was suggested that not only slag liquid fraction but also liquid fraction of reduced metal is necessary to improve the recovery efficiency.