Abstract: This study aimed at the examination of nutrient enrichment of cassava peels and corn cob through mannanase treatment. Mannanase production was conducted using Locust Bean Gum (LBG) as the sole carbon source; moisten with mineral salt solution and enzyme activity determined by dinitrosalicylic acid. Crude mannanase was concentrated by ammonium sulphate. The samples were hydrolyzed with concentrated mannanase within a sealing system. The chemical compositions of enzyme treated-samples were determined according to standard chemical methods. The mineral compositions of the enzyme-treated samples were determined using atomic absorption spectrophotometer method. The result obtained showed an increase in crude protein from 5.34±0.17% in non-enzyme treated corn cob to 9.61±0.98% in enzyme treated corn cob. The enzyme treated samples showed a markedly reduction in crude fiber by 13.75 and 29.70% for cassava peels and corn cob respectively. The lignin (9.49%), cellulose (68.75, 33.06 and 10.82%) and hemicellulose (55.38 and 9.64%) contents decreased in enzyme treated samples for cassava peels and corn cob. Cyanide decreased significantly in all the mannanase-treated samples. Mineral composition varied significantly with treatment type and the substrate treated. The treatment of cassava peels and corn cob with mannanase resulted in the degradation of the complex carbohydrate fractions in the samples to increase its crude protein and certain minerals contents.