Abstract: The effect of aqueous extracts of five wood samples: Khaya grandifoliola, Mansonia altissima, Brachystegia eurycoma, Milicia excelsa and Terminalia superba on some cellulolytic bacterial strains was investigated. The aqueous extracts of the wood samples inhibited the growth and cellulolytic activity of the Bacillus subtilis strains to varying degrees. The inhibitory effect of the extracts of Brachystegia eurycoma against the bacterial strains was highest when compared to the other wood types.