Effect of Cocos nucifera and red chilli on intestinal B-glucuronidase and faecal mucinase activity, was studied in rats given 1 ,2-dimethylhydrazine (DMH) . The average weight gain by the animals given coconut kernel was more than the DMH and chilli treated groups. The activity of B-glucuronidase decreased in the kernel groups, in most of the tissues studied, as compared to the DMH and chilli treated groups. A similar pattern was observed in the case of mucinase. Morphological studies showed that the number of visible malignant tumours decreased in the colon and intestine of the animals, when their diet was supplemented with coconut kernel. Histopathological studies also showed that the animals had fewer papillae, lesser infiltration into the sub-mucosa and lesser changes in the cytoplasm with decreased mitotic figures, when kernel was included in the diet. Coconut kernel, thus reduced the mutagenic and carcinogenic effect of chilli and DMH respectively.