A comparative study was carried out to investigate the efficacy of the aquous extract of Terminalia avecinnoides alone and its combination with diminazene aceturate. Thirty Wister albino rats of both sexes weighing between 250 -260gms were distributed into six groups (A-F) of five rats each. All the rats in groups A-E were infected with 0.5ml of blood containing 1x106 Trypanosoma brucei brucei. Rats in group F were uninfected and untreated (control). Rats in groups A -D were treated 5 days post-inoculation orally, with 3.5mg/kg Berenil alone, 80mg/kg plant extract alone, 80mg/kg extract plus 1.75 mg/kg Berenil and 1.75 mg/kg Berenil respectively were infected Group E, not treated. Treatment with extract alone resulted in reduction in parasitaemia, but was not curative. However, Berenil treatment alone and its combination with the extract resulted in the clearance of the parasite.The result obtained suggests that T. avecinnoides alone and its combination with Berenil offer great potentials as alternative products for the treatment of trypanosomiasis.