Abstract: The leaves of cassava have rich total flavonoids, and also contain toxic substance——cyanide, which severely restricts the utilization of cassava leaves. To take off the cyanide and retain the total flavonoids in cassava leaves, drying method was used in this study. The drying temperatures were set at three gradients as 65℃, 75℃ and 85℃, and the drying times were set at three gradients as 6 h, 7 h and 8 h, in total, there were 9 experiments. The content of total flavonoids was determined after drying processing of every experiment. The results showed that the optimum condition for taking off cyanide was 75℃ and 6 h. Under this detoxification condition, the content of cyanide was in accord with the National Standard, and the loss of total flavonoids was relatively low. The results could provide a reference for the comprehensive utilization of cassava leaves.