This research proposal aims to design a legged robot based on the variable stiffness mechanism. The variable stiffness mechanism can enable the robot to change its stiffness based on the terrain it is navigating. This design can improve the robot's stability, mobility, and energy efficiency. The proposed research will investigate the feasibility of the design and develop a prototype of the legged robot with variable stiffness. The research aims to contribute to the field of robotics by improving the design of legged robots, which can have various applications in search and rescue, agriculture, and exploration.