ABSTRACT Humanoid robots operating in unstructured environments and under high‐load conditions commonly face challenges such as limited locomotion performance and the difficulty of balancing structural strength with weight reduction. This study proposes a novel bio‐inspired electro‐hydraulic humanoid robot that incorporates a parametric dynamic model based on the coupled muscle–tendon–bone characteristics of the human hip–knee–ankle complex. Leveraging a custom‐designed, reverse–inverse kinematics framework, the leg morphology and electro‐hydraulic actuator parameters are co‐optimized to enhance agility and obstacle‐crossing capabilities. To simultaneously ensure structural strength and mass control, honeycomb structures are designed for the leg components, achieving functional lightweighting while preserving balanced strength across different directions. Simulation analyses demonstrate that a 21.28% weight reduction is attainable while maintaining comparable out‐of‐plane equivalent elastic and shear moduli relative to the original structure, thus meeting the demands of complex loading and impact conditions. Experimental tests confirm that the robot exhibits robust environmental adaptability and stable locomotion during high‐speed running at 10 km/h and obstacle traversal over 300 mm. The findings validate the effectiveness of the proposed configuration and bio‐inspired strategy, providing theoretical support and an engineering paradigm for structural optimization and system integration in high‐performance humanoid robots under complex task scenarios.