Objectives: Typhoon rainstorm is an important factor inducing geological hazard in southeast coastal area of China. In August 2013, The typhoon “Utor”landed in Yangjiang city, Guangdong province, which caused large debris flow disaster in Tieshanzhang Mining area, and the personal and property safety of downstream residents was directly threatened. Mine debris flow belongs to artificial debris flow. At present, the researches on mine debris flow are more emphasis on the evaluation of its risk (J. A. Ballesteros et al. 2016; Samygarcíatorres et al. 2017), but the study of mine debris flow in typhoon rainstorm is much less (Fan Shufang et al., 2017). Therefore, it is necessary to study the formation conditions, starting mode, and movement characteristics of it, which will be of great significance for its prevention and mitigation.Methods:We analyzed and studied by field investigation and tests. The area of the research region was about 5.53 km2. The field investigation focused on geological conditions, source conditions, and hydrodynamic conditions; The exploration methods and technical means included topographic survey, typical section survey and mapping, drilling engineering, geophysical prospecting engineering and debris flow unit weight proportioning test, water quality analysis, and so on. According to site requirements, 35 boreholes were drilled, with a total drilling meterage of 1099.4 m; a heavy dynamic penetration test was conducted in 6 places to determine the rock and soil mechanics parameters of the deposits。To determine the overburden thickness of waste rock and waste soil accumulation slope, 12 sections with a total length of 2.73 km were constructed using resistivity method; to determine the unit weight of debris flow, 6 groups of field debris flow unit weight proportioning tests were conducted; 6 groups of 12 water samples in the main gully and each branch gully were analysed. We collected and sorted all of the rainfall data of Guangdong province during the typhoon——‘Utor’ period, and analyzed the characteristics of typhoon rainstorm. Results:The debris flow in Iron Mountain is in the stage of youth development, which belongs to rainstorm, high frequency, dilute nature and mine debris flow. Disorderly mining and slag random stacking provide the source condition for the formation of debris flow, and Typhoon rainstorm is the direct factor of the largescale debris flow eruption. The total amount of solid source is about 9.3517 million m3, of which the channel accumulation is about 6.4827 million m3. At the g11—g11′ of the main Groove section, the flow rate is 2.85m/s, the peak flow 314.27m3/s, the total amount of 149,300 m3, the punching pressure is 16.4kPa, it is easy to discharge the debris flow over the dam, expand the disaster scale, and its starting mode is sliding collapse—blockage—burst type. Conclusions: This paper analyzes and studies the gully characteristics, source characteristics, forming conditions and starting mode of debris flow during typhoon rainstorm in the mine of Iron Mountain, and it can effectively reduce the risk of debris flow disaster to control the dumping slope in the upstream of the river basin and regularly clean the waste residue occupying the flood passage in TieShanZhang Mining area,which is of great significance to the prevention and mitigation work in similar disasters.