EDTA form metal-EDTA complexes which have its effectiveness in mobilizing of the contaminant metal ions, especially cadmium. This work was  carried out to investigate the effect of the ion –exchanging (chelating) agent EDTA on cadmium (Cd) toxicity and its impact on haematological and biochemical changes in catfish (Clarias gariepinu)).  The fish  (160-180g ) were exposed to 12 ppm Cd alone  or with 0.1, 0.2 and 0.3 g EDTA/L for 3, 10 and 45 days.  Cd exposure reduced significantly (P<0.05) erythrocyte count (RBCs), haemoglobin content (Hb), haematocrit value (Hct), mean cell volume (MCV) mean cell haemoglobin (MCH) and mean cell haemoglobin concentration (MCHC). These parameters were  improved  when EDTA was applied with Cd. The values of  RBCs , Hb, Hct, MCV, MCH and MCHC were increased significantly to be as in the  control fish group.   There was significant decreases in plasma  total protein (TP) in fish exposed to Cd alone. The levels of  plasma glucose,  total lipids (LP), aspartate  aminotranseferase (AST), alanine aminotransferase (ALT) were increased significantly in fish exposed to Cd alone. Addition of EDTA to Cd contaminated medium enhanced biochemical parameters in fish and the enzyme activities returned  to be as the control fish group.        Addition of EDTA to Cd contaminated medium considerably reduced metal absorption and its accumulation in fish tissues, and  reduced  metals in water.  Fish exposed to Cd alone accumulates 2.93, 4.33 and 7.2 mg Cd/g dry weight in body fish  for 3, 10  and 45 days, respectively. Cd was reduced significantly  to 0.13, 0.17 and 0.22 mg Cd/g dry weight in fishes exposed to 0.1, 0.2 and 0.3g EDTA/L for 3,10 and 45 days, respectively these values were  similar to those of  control group.