With the tartary buckwheat bran as material,the effect of subcritical extraction time,extraction kettle temperature and system pressure on total flavonoids content were analyzed by combination of single factors experiment and orthogonal experiment.During the extraction of total flavonoids by subcriticaland ultrasonic,these indices affected the extracting efficiency in the following orders: extraction kettle temperature>subcritical extraction time>system pressure.The optimal extraction conditions for flavonoids from tartary buckwheat brans were extraction kettle temperature 20℃,subcritical extraction time 3h and system pressure0.8MPa.Under these optimum conditions,yield of total flavonoids reached 90.05%.