Abstract: Snow avalanche is one of frequently occurred naureal hazards in Tibet area and there are reports about fatalities cauced by snow avalanche almost every year and this trend is increasing under global climate warming. There are two regions with the highest frequency of snow avalanches in Tibet. One is Nyainqentanglha mountains and its southeastern extension and another is the southern slope of the Himalayas. The development of snow avalanche is restrained due to less precipitation and it only exists in alpine snow-covered mountains and glaciation area in the plateau interior of Tibet. The area of perennial avalanche prone region in Tibet is very limited, accounting for only 1.6% of the total area of the plateau. Snow avalanche in Tibet mainly occurs in winter and spring. Avalanche prone areas in winter account for 2.9% of the total area of Tibet, and this rate increases to 3.3% in spring. Snow avalanche is one of the most dangerous natural hazards to the road safety in Tibet, in which Anjula-Guxiang section of Sichuan-Tibet highway in the eastern Tibet and Lalongla-Friendship Bridge section of Sino-Nepal highway in the southern Himalyans are two roads that most severely impaced by snow avalanche. Due to technology advancing of hazard prevention and control engineering and its implementation in key road sections in moutanous Tibet, the threat from snow avalanche to road traffic safety has been greatly reduced over last 20 years. However, with the increase of human activities such as mountaineering and leisure tourism in alpine snow-covered mountains, the casualties and economic losses caused by snow avalanche hazard are increasing year by year. Therefore, in addition to the continuous implementation of engineering prevention and control measures in key regions such as Sichuan-Tibet highway and railway sections, enhancing the service level of monitoring, early warning and forecasting is an important way to prevent and mitigage snow avalanche hazards in Tibet based on detailed investigation and division of avalanche hazard in key snow avalanche impacted areas.