text: The action of fresh minced garlic and garlic oil on aflatoxin B1- (AFB1) induced carcinogenesis in the toad Bufo regularis was studied. Feeding toads with AFB1 induced tumors in 19% of the animals. Animals given AFB1 together with fresh garlic or garlic oil showed a significant reduction in tumor incidence. The tumor incidences were 3% and 9% in animals given AFB1 plus garlic and AFB1 plus garlic oil, respectively. In all three groups, the tumors were located in the liver (hepatocellular carcinomas), in addition to the kidney in animals treated with AFB1 alone and together with garlic. The kidney tumors were diagnosed as metastatic deposits from the primary liver tumors. It is speculated that one or more constituents of garlic may be responsible for inhibition of AFB1-induced carcinogenesis in B. regularis.