Abstract: This study was conducted to investigate haematological changes in the blood of Clarias gariepinus fed diets containing Chrysophyllum albidum seedmeal replacing maize. Five isonitrogenous diets containing maize, which was replaced by Chrysophylum albidum at a rate of 0, 25, 50, 75 and 100% were made. The diet without Chrysophylum albidum seedmeal served as the control. Experimental diets were assigned randomly to the tanks and each group of fish was fed 5% body weight in equal proportion per day. The fish fed diet 1 had the highest PCV while the fish fed diet 3 had the lowest PCV. There was significant difference (p<0.05) in the PCV of the fish fed various dietary treatments. However, there was no significant difference (p>0.05) in the PCV of the fish fed diet 2, 3, 4 and 5. A similar trend, as observed for PCV, was also observed for Hb, RBC, MCV, MCH and MCHC. There was no significant difference (p>0.05) in the WBC of the blood of the fish fed various dietary treatments so there were also neutrophyls and lymphocytes.