An improved A* algorithm is proposed to address the issues of tortuous paths， proximity to obstacles， and low search efficiency in global path planning for wheeled inspection robots. First， the cost function of the A* algorithm is optimized to enhance path accuracy. Second， a line-of-sight method incorporating a distance factor is employed to reduce the tortuosity of the global path and increase the safe distance between paths and obstacles. The two-way search strategy is utilized to improve search efficiency. Finally， the global path is smoothed using quasi-uniform B-spline curves. The environment map is modeled using the grid method， and the algorithm is applied to a chlor-alkali chemical inspection robot scenario. Experimental results demonstrate that， compared with the traditional A* algorithm， the improved A* algorithm exhibits superior performance in terms of path safety， and the number of path inflection points. Specifically， the number of path inflection points is reduced by 79.41%. The global path generated by the improved A* algorithm is smoother， better satisfying the requirements for path planning in wheeled inspection robots.