Abstract: The antimutangenic and antitumor effect of buckwheat sprout extracts were studied to provide scientific basis for exploiting health function of buckwheat sprout. Antimutangenic effect of buckwheat sprout extracts were testified based on the mice bone marrow cell micronuclei test. Antitumor effects of buckwheat sprout extracts were testified based on S-180 tumor cell transplanting test. The micronuclei frequency induced by MNNG in mouse bone marrow cells was inhibited significantly by buckwheat sprout extracts. Under 80mg/kg, buckwheat ethanol extract, ethyl acetate extract and butanol extract on mouse bone marrow micronucleus inhibition rate reached to 73. 4%, 75. 8%, 74. 2%. Buckwheat sprout extracts on the growth of transplanted tumor of mouse S-180 also had the obvious inhibitory action, including buckwheat sprout ethanol extract, ethyl acetate extract tumor inhibition rate reached to 39. 5%, 38. 0%. Buckwheat sprouts had preventive effect on DNA damage in body cell, and had inhibitory effect on tumor growth.