Casting crane is a machine that relies on longitudinal movement along the direction of the factory track, lateral movement of the trolley and lifting movement of the hook. The small frame is one of the main components of the crane which accounts for 16% of the total weight of the crane and plays a major role in carrying. Therefore, designing a reasonable small frame structure is of great significance to the overall safety and economy of the crane. This paper takes 10 tons of cast crane frame as the research object and designs a new frame with 3D printing technology as the main processing method. Firstly, the coordinate system is established with the frame steel plate as the coordinate plane, and the coordinate system is input according to the position of the reducer seat, the motor base, the fixed pulley, etc. on the frame, and the position and size of the cutting are determined, combined with ANSYS finite element analysis. The software optimizes the frame by analyzing the stress and deformation of the overall structure of the frame. The results show that the crane frame designed by 3D printing technology has the same strength as the original crane frame and the weight loss is 169 kg, and the weight loss part accounts for 17.4% of the weight of the improved front frame.