The in vitro and in vivo anti-trypanosomal activity of aqueous and methanolic extracts of bark of Ximenia americana was examined in mice experimentally infected with Trypanosoma congolense. Thirty (30) healthy mice were infected with T. congolense at 10 4 and subsequently treated in vitro with aqueous, methanolic and Diminavet R extract at 3, 6,and 9mg/ml and in vivo with aqueous stem bark extract at 50, 100, 200 and 300mg/Kg body weight and Diminavet R at 3.5mg/kg body weight respectively. The result showed that in vitro incubation of infected blood with methanolic extract immobilized the parasites at a concentration of 9mg/ml. In vivo study also showed the aqueous extract at 50, 100, 200 and 300mg/Kg body weight were parasite free for 1,5,7 and 14 days respectively. The effect of the extract appeared to be dose dependent. The results showed that Ximenia Americana had in vitro and in vivo efficacy by suppressing the growth of the parasites followed by a relapse.