Trypanosoma evansiwas isolated from cattle, goats, horses in 6 provinces of Vietnam. It was tested to determine its efficacy to some medicines in vivo and in vitro conditions. The studied results showed that: Trypamidium samorin was a highest effective medicine for treating T. evansi
diminavet and azidin were the lower effective medicines to treatment of T. evansi
trypanosoma was the lowest effective medicine to kill T. evansi in vivo as well as on experimental white mice. In other words, T. evansi is very susceptive with trypamidium samorin medicine, lower susceptive with diminavet and azidin medicines, and resistant to trypanosoma medicine. Safety and treatment effectiveness were obtained when using a higher effective medicine dose than recommended dose of the manufacturer for testing experimental animals to disease caused by T. evansi.