1. From the view of scenery: If you go to Tibet in March or April, you can go to Nyingchi to enjoy the sight of peach blossom. Mountains are full of wild peach trees at this time, especially beautiful. In June, July, August and September, because it is very hot in mainland China, you can go to Tibet to avoid summer heat, and the scenery here is the most beautiful during this period of the year. These months are regarded as the peak season, of which, July and August are the most popular because the scenery at this time is the best. 2. From the view of passenger flow in Tibet: July and August are the peak season when there are many people here and consumption is more expensive. If you lay stress on passenger flow and consumption, it is better for you to choose June or September. 3. From the view of climate: The annual precipitation of Lhasa is 200?510 mm, which is concentrated from June to September. Night raining is more frequent. The highest temperature is 28 ℃ and the lowest temperature is minus 14 ℃. The air is thin, the daily temperature range is large, and it is dry and windy in winter and spring here. Relatively speaking, March to October features a warm and humid climate, and is the best season for Tibet tour, but usually the May Day is the beginning of the travelling season in each year.