In order to study the influence of flash groove structure on die forging of crankshaft, the suitable flash groove structure was determined by numerical analysis and test verification. Firstly, three typical structures of conventional flash groove structure, flash groove structure of resistance  ditch and flash groove structure of resistance wall were analyzed, and the corresponding metal flow characteristics in the die forging were studied. Secondly, the corresponding analysis models were constructed, and the influences of three different types of flash groove strustures on the mold filling, stress and strain distribution of forgings and the maximum forming load were comprehensively analyzed by Deform. Finally, the analytical results were verified by experiments. The results show that by applying resistance wall of flash groore structure, the ability of mold filling is effectively improved when other results have less effects, which could realize the precise blanking and save the cost of materials.