Abstract: To address high reliability demands for power and communication transmission in in-situ uranium leaching operations, an optical-electrical composite cable specifically designed for underground environments was proposed. In the paper, design principles and key technologies of the composite cable were outlined, tailored to the unique requirements of uranium leaching. Through optimization of the cable’s structure, material selection, and manufacturing process, stable performance was achieved under the extreme conditions typically encountered underground. Test results indicated that tensile strength of the optical-electrical composite cable was 2510 N, and bending radius was 80 mm. Compared to traditional separate power and fiber optic cables, the integrated optical-electrical composite cable could offer significant improvements in wiring efficiency and failure reduction.