As a third-generation automobile steel,the enhancement of mechanical properties and formability for the medium-Mn steel is becoming a cutting-edge topic. In this research,a warm-hot stamping process for the medium-Mn steel is proposed. The methods of orthogonal experiments,range analysis and comprehensive evaluation are used to investigate the optimal process parameters. The warm-hot stamping process with austenization temperature of 810 ℃,soaking time of 7 minutes and deformation temperature of 550 ℃ are optimal. Tear tests show that the fracture morphologies are uniformly distributed and fine-grained martensite laths with the average size of 2-3 μm are observed when the optimal process parameters are applied. Moreover,an automotive B-pillar is warm-stamped to examine the new process. The excellent comprehensive performance including strength,plasticity and fracture toughness is achieved. As a result,the warm-hot forming process for the medium-Mn steel is proved to be effective and will promote the industrial application of the third-generation automobile steels.