Abstract: An investigation was conducted in a 2 x 4 factorial experiment to evaluate the effect of Cottonseed Cake (CSC) with or without vitamin-E supplementation on the haematological parameters of pre-pubertal rabbit bucks. The experiment involved 8 treatment combinations comprising four CSC levels (0, 5, 10 and 15%) and two vitamin-E supplementation levels (0 and 30 mg/kg diet) denoted as minus (-) vitamin-E and plus (+) vitamin-E. A feeding trial lasted for eight weeks after which blood was collected from the animals and analyzed for Haemoglobin concentration (Hb), Packed Cell Volume (PCV), Red Blood Cell Count (RBC) and White Blood Cell Count (WBC). Analysis of variance showed that CSC had significant (p<0.05) depressing effect on Hb, while WBC values increased (p<0.05) with increasing level of CSC. The PCV and RBC were not significantly affected by CSC. Vitamin-E supplementation did not have significant (p>0.05) effect on the haematological parameters of the rabbit bucks. Interaction effect of CSC and vitamin-E did not affect (p>0.05) HB, PCV and RBC while only WBC was significantly (p<0.05) affected by the interaction effect. It was concluded that CSC had adverse effect on some haematological parameters and that vitamin-E showed a tendency to correct the adverse effect. Probably a higher dose of vitamin-E is required to elicit a greater ameliorative affect.