Changes in some blood biochemical parameters were studied in the juvenile and adult sizes of freshwater fish C.gariepinus under different saline exposure (0.00-control; 0.50; 1.00; 1.50; 2.00 and 2.50ppt) for a period of 15 days. The blood biochemical parameters evaluated werealbumin, total protein, lipids, total bilurubin, urea, creatinine and globulin. The results obtained indicated a significant (P<0.05) reduction in the values of total protein, lipids, total bilurubin, creatinine and globulin. While the values of urea increased considerably in both sizes of the fish. However, albumins were within the same range in all concentrations of exposure. Thus it indicates that although fish survives and able to tolerate saline conditions. The variations of blood biochemical parameters can be considered as a kind of saline stress response particularly on metabolites.