Abstract: Falling accidents from high altitudes involving external construction scaffolding occur frequently, having become a major risk source threatening the lives and safety of construction workers. Clarifying whether safety fall arresters can serve as an effective protective measure and reduce the casualty rate of falls is a key issue that urgently needs to be addressed to improve the safety level of the industry. This paper aims to conduct an in-depth exploration of the application value of safety fall arresters in external scaffolding operations of construction projects. Through methods such as literature research, statistical data analysis, on-site investigations, and case verification, it systematically analyzes the working principles, types, and characteristics of safety fall arresters, sorts out the specifications for their installation and use, evaluates their protective effects and the root causes of failures, and conducts research based on sampling survey data from 50 ongoing projects in the Guangzhou area. The results show that compared with the traditional safety belt, the safety anti-falling device has significant advantages: the wearing rate jumps from 38% to 92%, and the effective working time per day is extended by 31%; in the event of a fall, the injury can be controlled at the ' slight ' level. Although a single project needs to increase the safety investment of about 80,000 yuan per year, it can reduce the direct accident loss of 1.2 million yuan, and the payback period is less than three months. However, the equipment rate of anti-falling device in the external scaffold operation site in Guangzhou is only 38.6%, more than half of the operators are not standardized, and 23% of the equipment is not tested on schedule. Practice has proved that the anti-falling device is feasible in both technical and economic aspects, which can effectively improve the anti-falling level of external scaffold. Construction enterprises should combine the specific conditions of scientific selection, and strictly implement the installation, use and maintenance management procedures. In the future, as the anti-falling device upgrades to the direction of intelligence and lightweight, it will help the construction industry to achieve safe development to a greater extent.