Abstract: The toxicity effect of excess palm kernel cake and the effect of phytase and zinc supplementation on palm kernel cake (PKC) toxicity in sheep were investigated. Three experimental diets A, B, and C were prepared using grass and PKC at 10% and 90% respectively. Diet A contained grass and PKC only (PKC group). Diet B was same as A but in addition was supplemented with RonozymeTM P at 750 FYT/Kg (PKC + Phytase (P) group). Diet C was also as A, but in addition, was supplemented with zinc sulphate at 500µg/g (PKC + Zn group). Another diet D, containing corn and fish meal at 20% and grass at 80% served as control. These diets were fed to twelve male West African Dwarf sheep (average weight 20.0±0.8kg) divided into 3 groups and the control. Clinical signs and body weights were monitored for 20 weeks. The animals were slaughtered and the right lobes and renal cortex were isolated for copper and Zinc estimation and histopathological evaluation. The results obtained showed that animals in the PKC + phytase group, PKC + Zinc group and the control performed alike in terms of clinical signs, gross and histopathological lesions. In terms of body weight gain, animals in PKC + phytase group performed better than animals in PKC + Zinc group and the control, although the differences were not statistically significant (p>0.05). Animals in the PKC group all died of PKC toxicity. Supplementation with zinc and phytase prevented chronic PKC toxicity and can be useful in the therapy for PKC toxicity in sheep.Supplementation with zinc however, led to significant elevation in zinc concentration in the liver and kidney. It is interesting to discover that the use of phytase did not elevate the concentration of zinc in these organs.