The Acacia seyal Dell family Mimosaceaeis is known locally as Talha tree. Many medicinal uses such as treatment of dysentery, leprosy, colds, diarrhea, hemorrhage, ophthalmic, intestinal ailments, rheumatic pains, colds and fevers, have been attributed to this tree. Schistosomiasis, a water-borne parasitic disease caused by Schistosome(s) a genus of digenetic trematode worms, infects man and animals in tropical and sub tropical regions. It is the second most prevalent parasitic disease in the world ranked only after malaria regarding the number of people infected and those at risk. More than 90% of the cases are occurring in Africa. The purpose of this study was to investigate the molluscicidal activiat ty of Acacia seyal bark methanolic extract against the snail Biomphlaria pfeiffer. Different concentrations (1000, 500, 250, 125, 62.5, 31.25, 15.625, 7.8125 and 3.91 ppm) of the Acacia seyal bark methanolic extract, were investigated in vitro  against snail Biomphlaria Pfeiffer. A. seyal bark methanolic extract exhibited 100% mortality within 24 h, only at a concentration of 1000 ppm; and  exhibited 100% mortality within 48 h, at 1000, 500, 250, 125 and 62.5 ppm. The IC₅₀ of bark of A. seyal at 24 h and 48 h was 80.79 and 34.33 ppm, respectively. These findings prove the potent in vitro activity of A. seyal (bark) methanolic extract against Biomphlaria pfeiffer.