Abstract: The mechanical properties of the casing head products of wellhead equipment always fail to meet the process requirements after quenching and tempering treatment. The φ125 mm equivalent test bar was used as the research object for experimental analysis. The results show that the mechanical properties of the product can be improved and the qualified rate of the product can be greatly improved by improving the quenching method, increasing the content of alloy elements and controlling the tempering temperature according to the carbon content of the material.