Trypanosomosis is a debilitating, fatal disease of man and animals often associated with anaemia. The trypanocides currently used in the management of the disease are far from giving desired results. This study investigated changes in haematological indices and the treatment outcome of diminazene aceturate (DA) against Trypanosoma brucei in dogs supplemented with resveratrol. A total of twenty (20) male Nigerian local breed of dogs (NBD) aged 6 to 12 months were used for the study. The dogs were randomly assigned into five groups (I-V) of four dogs per group. Group I was uninfected and unsupplemented; group II, was infected, untreated, and unsupplemented; group III, infected unsupplemented, treated with DA, group IV was infected and supplemented but untreated with DA, and group V was infected and supplemented DA-treated. The mean pre-patent period of Trypanosoma infection was 5.75±0.96 and 9.00±0.82 days for the infected unsupplemented and the infected resveratrol-supplemented groups, respectively. There was a complete parasite clearance from peripheral blood within 24-48 hours following treatment with DA on day 10 post-treatment (PT) in the supplemented and 24-72 hours in the unsupplemented treated groups. The supplemented treated did not show any relapse of infection, whereas the un-supplemented, DA-treated showed relapse on day 25 PT. It was concluded that resveratrol supplementation enhanced the efficacy of diminazene aceturate with no risk of relapse, minimized the effects of the parasite in the animals, and increased survival time.