Duplex stainless steels (DSS) composed of ferrite and austenite have an attractive combination of mechanical and corrosion properties. Commercial DSS contain a considerable amount of Ni ranging from 4 to 7 wt.%. In recent years, efforts have been made to develop lean DSS with reduce Ni which can provide substantial economical savings and improve mechanical properties due to transformation-induced plasticity. In the present study, several kinds of lean DSS with unique chemical composition were fabricated, and the mechanical and corrosion properties were investigated with precipitation behavior. Based on the results, the lean DSS developed in KIMS showed an excellent combination of strength-elongation and good corrosion resistance.