Bt plants are insect-resistant plants engineered to carry the gene coding the insecticidal protein of a soil bacterium, Bacillus thuringiensis. These transgenic plants provide a highly effective method of insect control and reduce dependence on pesticide chemicals. In consequence, they have provided higher yields, reduced crop mycotoxin levels because of the effective lowering of the insect damage, and have decreased the pesticide spraying work and cost. However, there are public concerns about the safety of Bt plants for humans, animals and the environment. This review describes recent research on the safety evaluation of Bt plants, focusing on our results in the toxicological studies of Bt11 corn.