HC340/590DP steel with martensite and ferrite dualphase structure is one of the more material for car lightweight. Through the tissue analysis, it is found that the flanging and reaming performance of HC340/590DP steel is mainly determined by the distribution of martensite in the material. Martensite continuously distributed in the ferrite grain boundaries which encloses the ferrite therein contributes to the crack propagation. However, the islandshaped and discontinuous distributed martensite can prevent the crack from growing. By reducing the carbon content of material, and properly increasing the annealing temperature, the martensite is obtained in the form of islandshaped and discontinuous distribution. Furthermore, the forming process of front crossbeam was simulated by the numerical simulation software and the criterion of flanging and reaming. The cracking risk for flanging and reaming of front crossbeam is reduced from 1.13 to 0.85 with the improved HC340/590DP material. Thus, the forming requirements of front crossbeam was met, and the actual verification was obtained.