Abstract: To solve the problem of sound and light alarm and initiating alarm process based on abnormal situation of KJ405T underground worker management system, the abnormal alarm process based on a large number of collected positioning data is designed. Combined with Visual C++ programming technology, Timer timer and ADO.NET 2.0 database access technology are used to develop and implement the abnormal alarm process. The abnormal alarm process function of downhole operation personnel management system is based on KJ405T. This paper mainly introduces the design and implementation of the abnormal alarm process.