Four healthy bucks of the West African Dwarf breed aged between 24 and 30 months were used for this study. The bucks were first used as control and later as experimental animals upon being fed daily with oiled pumpkin plant for the period of six months. The objective of the study was to investigate the effect of the pumpkin plant on the morphology of the spermatozoa of the bucks. There were significant differences (p< 0.05) between the control and experimental values for both primary and secondary morphological spermatozoa abnormalities: the pyriform head has a control value of 6 (0. 42%) and post-feeding value of 0 (0%), the beat tail; 14(0.97%) and 2 (0.16%) for the control and post feeding values respectively. The curved mid piece: 17 (1.18%) and 1 (0.08%) for the control and post-feeding values respectively. The bent mid piece also differed significantly (p<0.05) between control value of 16 (1.11%) and post feeding value of 3 (0.23%). All through the stages of the study, there were significant reductions in the number of sperm cells with abnormalities consequent upon daily feeding of the animals with pumpkin plant. The plant is therefore recommended for both prevention and treatment of make infertility in man and animals.