Abstract: Aiming at the problem of surface cracks easily occurring during the forging process of 4Cr5MoSiV1 (ASTM H13) steel, for H13 steel end flange cup-shaped  forgings, its forming process was developed. Firstly, the true stress-true strain curve of H13 steel was obtained by high temperature compression test. Secondly, combined with the process test results, the flow law and stress distribution of the metal during the forging process were analyzed by finite element simulation software DEFORM-3D. Furthermore, the causes of cracks in the test sample were found out, and the measures such as controlling the temperature uniformity of billet and improving the shape of forgings were proposed. Finally, the trial production of a certain type of H13 steel cup-shaped part was realized through the process improvement. The test results show that H13 steel small forgings is prone to crack during the forging process. It is necessary to ensure the uniformity of billet temperature, control the consistency of forging deformation and the contact friction conditions, which has certain guiding significance for the development and production of small end flange cup-shaped part of H13 steel.