[Objective] Dandelion（Taraxacum mongolicum Hand.-Mazz.） is an important medicinal and edible herb distributed commonly in Xizang. To study the contents of total flavonoids, polysaccharides and other sugars, the main pharmacologically active ingredients in different dandelion species and analyze the effect of altitude and slope direction to the content will provide important guidance for the efficient exploitation and utilization of Tibetan dandelions resources. [Methods] Taking the whole herb of 6 species of dandelion, T. eriopodum (D. Don) DC., T. calanthodium Dahlst., T. sikkimense Hand.-Mazz., T. maurocarpum Dahlst. T. grypodon Dahlst., and T. stenoceras Dahlst. grew at different altitudes and slope directions in Tibet''s Shergyla mountain as the research materials, contents of total flavonoids and several sugars were measured and analyzed, respectively. [Results] (1) The total flavonoid content of T. eriopodum west slope-3 900 m (80.9 mg/g) was higher than that of the others, and the total flavonoid content of T. sikkimense east slope-2 300 m (29.08 mg/g) was significantly lower than that of the other samples（P<0.05）. (2) The total sugar content of T. grypodon east slope-2000 m reached as high as 440.55 mg/g with significantly different from that of the other samples，but T. sikkimense west slope-4200 m was the lowest to 63 mg/g, which was significantly lower than that of the other samples. (3) The highest content of reducing sugar was 61.1 mg/g and the lowest was 35.98 mg/g in all samples, but the difference between different species and different altitudes was not as obvious as total sugar. (4) The contents of polysaccharide in T. grypodon east slope-2 000 m and T. sikkimense west slope-3 000 m were high to above 320 mg/g, while the contents of T. sikkimense west slope-4 200 m as well as 3 900 m and T. eriopodum west slope-3 900 m were below 70 mg/g and significantly lower than that of the other samples. [Conclusion] The total flavonoids and polysaccharides in Tibetan dandelion were high, and had obvious difference among different dandelion species and further showed opposite change trend affected by altitude and slope direction, while the contents of polysaccharides and total sugars showed a similar pattern of change .West slope direction and the higher altitude were benefit to the accumulation of flavonoid usually, while the east slope direction and the lower altitude were benefit to the accumulation of polysaccharide.