Objectives : The objective of this study was to compare, the potency of toxicity of Cantharidin containing dried Mylabis phalerata (MP) extract and it's modifier. Methods ： They were monitored at dosage level 2,000, 1,000, 500, 250 and 125 mg/kg, respectively. Changes of body weight, clinical signs, mortality, LD50, macroscopic changes of gastrointestinal tract and liver were observed after single oral dose of test articles with changes of serum Gastrin and Somatostatin levels. Results ： Dosage-dependent decrease of body weight and/or gains were demonstrated in dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, the body weights were significantly increased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependently detected clinical signs in dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these clinical signs dramatically were decreased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependent increase of mortality rates were observed in dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, the mortalities were significantly decreased compared to that of equal dosage group of dried MP extract-dosing group. The LD50 of dried MP extract in male mice was dramaticlly increased in their modify, 265.86 vs 426.99 mg/kg. Dosage-dependently increase of number of hemorrhagic and/or erythematous spots detected in the gastrointestinal tracts of dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these abnormal spots were dramatically decreased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependently increase of degrees of enlargement and congestion detected in the liver of dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these abnormal signs were dramatically decreased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependently increase of serum gastrin levels of dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these abnormal increase were dramatically decreased compared to that of equal dosage group of dried MP extract-dosing group. Dosage-dependently increase of serum somatostatin levels of dried MP extract-dosing groups, were also detected in modified and dried MP extract-dosing groups at 2,000 and 1,000 mg/kg-dosing group. However, below 500 mg/kg-dosing group, these abnormal increase were dramatically decreased compared to that of equal dosage group of dried MP extract-dosing group. Conclusions ： The toxicity of dried MP extract was reduced by their modify.