The effects of roasted yam ( Discorea rotundata
Poir.) were studied on some hematologic parameters in male albino rats. Twenty four (24) adult male rats were divided into three groups of eight rats per group. Group I served as the control group, in which the rats were given normal rat chow. Group II rats served as the sham control and received normal rat chow mixed with 25% of finely ground yam, while group III served as experimental group and received normal rat chow mixed with 25% of finely ground roasted yam. At the end of the experimental period (6 weeks), animals in all the groups were sacrificed and blood samples were taken for the determination of red blood cell (RBC) count, hemoglobin (Hb) concentration, and packed cell volume (PCV) and erythrocyte osmotic fragility. It was observed that roasted yam ingestion reduced RBC count, PCV, and Hb concentration while it increased erythrocyte osmotic fragility rats (p<0.05). Ingestion of non-roasted yam did not have effect on the measured hematologic parameters. It is therefore concluded that ingestion of roasted yam might have a deleterious effect on some hematologic parameters.