The paper introduces the design and testing of a tank-like modular wall-climbing robot (WCR). Firstly, a bioinspired dry adhesive patterned with papilla-like array is fabricated, and its quasi-static adhesive properties is tested and evaluated. Based on the material’s properties, a single tank-like module using timing adhesive belts is optimally designed for maximum adhesive force. An under-actuated four-bar compliant linkage is utilized to connect the two modules of the WCR. The lengths of the linkage are optimized in keeping both of the modules having constant preloading forces on surfaces with different inclinations. Experimental results show that the compliant link functions like the digital joint of the gecko that is able to maintain enough preloading force for each module on the surfaces of variable inclinations, making the robot adapted to surface transitioning easily.