Abstract: This paper focuses on the comprehensive application of handheld 3D scanning technology in underground mines. This technology is practical and easy to operate, which is essential in the production and management of underground mines, and plays a significant in geological exploration, surveying and mapping, mine safety and other fields. Its wide application simplifies the traditional measurement and modeling process, and improves the accuracy and timeliness of data. In terms of geology, with the ability of high-precision detection, it reveals geological structure, defines the boundary of ore body, and collects geological data, which support for geological analysis and resource evaluation. In the field of surveying, the advantage of rapid scanning is used to complete the survey of mine shaft engineering, determine the distribution of goaf, and monitor the deformation of the mine, which provides protection for the planning and implementation of mine engineering. At the same time, the technology is used for hidden danger investigation of safety, auxiliary decision-making of emergency rescue, safety training and other work, and the training effect is improved and the safety awareness and emergency ability of personnel are enhanced by displaying three-dimensional models. This technology has improved the efficiency of underground mine exploitation, optimized the utilization rate of resources, and improved the safety management level, which provides protection for safe production and sustainable development of mines.