Two sets of experiments were conducted for domestic sewage treatment by using Actizyme, a commercial biological product, at a ratio of 1.5 g/61 of waste water. The product consisted of Bacillus subtilis and four enzymes : amylase, lipase, protease and cellulase. The Actizyme treated groups and the untreated control were left for 7 days and BOD₅ determined. The BOD₅ of the Actizyme treated groups was found to be significantly reduced by 68.11% and 79.39% at 95% and 99% confidence level respectively when compared with the untreated control. The Actizyme treated groups showed an increase in pH, reduction in turbidity and odor.