The efficacy of autoclaved cercarial vaccine (ACV) in eliciting protective immunity against Schistosoma mansoni infection was investigated in Swiss strain Albino mice. Two main groups of animals were used. One served as control group and the second was vaccinated with ACV mixed with Bacille Clamette-Guerin (BCG) as an adjuvant, in a single, double and triple doses 2 weeks apart. Six weeks after the first vaccination, all animals were challenged with freshly liberated cercariae of Schistosoma mansoni then sacrificed 7 weeks later. Parasitological, histopathological and immunological studies showed promising results which gave hope in evolution of anti-schistosomal vaccine.