Overlay draped net system, works as a rockfall and debris guidance system, is utilized on the rock slope where contains unstable and loose debris. The motion trail of falling rocks and debris can be limited and controlled by the high-intensitive flexible steel mesh covered on the target slope. This system can prevent the splashing and bouncing of falling rocks and debris which threat the protected area, and all the falling objects guided and collected in the accumulation area at slope foot are easy to clear and maintain. The draped net system reduces the onsite operation and lowers the risk of construction on steep and unstable slope. Cost-effective and easy construction enable this system applied to most of slope treatment conditions.