Abstract: In this paper,the 3 d germinated buckwheat was used as the material. Effects of light quality(red light,yellow light,green light,white light,blue light,UV-A(356 nm) and UV-C(254 nm)) on flavonoids,antioxidant properties and relative enzymes of flavonoids for treating germinated tartary buckwheat. The results indicated that total flavonoid and rutin content in buckwheat sprouts was significantly increased under the treatment of ultraviolet,blue,white,yellow and red light in the germination process(compared with the dark treatment),and there was significantly different between the different treatment(p<0.05). After the treatment of UV-C,total flavonoid and rutin contents in buckwheat sprout were the highest,and increased 30.1% and 40.9% compared with the control group, respectively. Moreover, activity of the key enzymes( PAL and CHI) of flavonoids metabolism in buckwheat sprout were significantly increased,and positive correlated with the contents of total flavonoid and rutin,after the treatment of light. These results demonstrated that after the buckwheat sprout treated with light,the contents of flavonoids were increased by improving the activity of key enzymes in anabolism process of flavonoids. In addition,the DPPH free radical scavenging activity of buckwheat sprout could be increased by the light treatment,and increased up to 35.1% in the process of buckwheat germination. The scavenging activity was positive correlated with the total flavonoids content,and indicated that the flavonoids content in buckwheat sprouts could be increased by the light treatment to improve the antioxidant activity of buckwheat.