Abstract: TWIP steel controls stacking-fault energy to create twinned crystal organizations, enhancing ductility and strength. Although extensive research has been conducted on TWIP steels fabricated by melting, limited attention has been given to TWIP steels prepared through powder metallurgy. Furthermore, the current powder metallurgy TWIP steel samples have not fully realized their vast application potential. The materials were prepared at different temperatures and times using a combination of gas-atomized Fe-21Mn-0.7C alloy powder and fast hot pressing technology. The effects of sintering temperature and sintering time on the tissue evolution and mechanical properties of the materials and subsequent hot rolling and heat treatment to further optimize the comprehensive mechanical properties were investigated. The results show that the temperature increases, the holding time increases, the small particle size range powders are fully fused together to form a denser structure, and the grain boundary oxides have basically been depinned. At 930 °C, 40 MPa, and 12 minutes, the alloy achieves a density of 98.86%, tensile strength of 955 MPa, and extensibility of 32.8%. After hot rolling, the tensile strength can reach 1 690 MPa. After annealing, a high-strength and high-toughness steel with excellent comprehensive mechanical properties is obtained, with the tensile strength and elongation being 998 MPa and 46.2% respectively. The annealed material exhibited excellent comprehensive mechanical properties.