OBJECTIVE: To optimize the extraction technology of total flavonoids from Aster souliei. METHODS: Atmospheric pressure closed hypoxia tolerance test of mice was used to screen the solvents (water, 60% ethanol, 95% ethanol) for the extraction of total flavonoids from A. souliei. Using extract yield and the content of total flavones as index, single factor test and orthogonal test were used to screen the amount of solvent, extraction time and extraction times. The validation test was also conducted. RESULTS: When the extraction solvent was water, the survival time of the mice was the longest. The optimized extraction technology was as follows as 12-fold water, extracting for 2 times, lasting for 2 h each time; average content of total flavonoids in validation test was 29.70% (RSD=0.54%,n=3) and extract yield was 24.58% (RSD=0.48%, n=3). CONCLUSIONS: The optimized extraction technology is stable and feasible, and can provide scientific evidence for the development and utilization of total flavonoids from A. souliei.