The integrated valve-controlled cylinder combines various control and execution components in hydraulic transmission systems. Its precise control and rapid response characteristics make it widely used in mobile equipment for aerospace, robotics, and other engineering applications. Additive manufacturing provides high design freedom which can further enhance the power density of integrated valve-controlled cylinders. However, there is a lack of effective design methods to guide the additive manufacturing of valve-controlled cylinders for more efficient hydraulic energy transmission. This study accordingly introduces an energy-saving design method based on additive manufacturing for integrated valve-controlled cylinders. The method consists of two main parts: (1) redesigning the manifold block to eliminate leakage points and reduce energy losses through integrated design of the valve, cylinder, and piping; (2) establishing a pressure loss model to achieve energy savings through optimized flow channel design for bends with different parameters. Compared to traditional valve-controlled cylinders, the integrated valve-controlled cylinder developed from our method reduces the weight by 31%, volume by 55%, and pressure loss in the main flow channel by over 30%. This indicates that the design achieves both lightweight construction and improved hydraulic transmission efficiency. This study provides theoretical guidance for the design of lightweight and energy-efficient valve-controlled cylinders, and may aid the design of similar hydraulic machinery.