Abstract: Ultraviolet-A radiation (320-400 nm) is scattered rapidly in water with biologically useful amounts to at least 100 m deep in clear aquatic environments. The present study aimed to elucidate the hematotoxic and genotoxic potential of UVA on the African catfish, Clarias gariepinus by investigate the impact of different UVA doses (3 h for 3 days and 5 h for 3 days exposure) on the hematological parameters, biochemical variables, micronuclei and binuclei formation. In the present result, a significant (p<0.05) decrease in Red Blood Cell counts (RBCs), Hemoglobin concentration (Hb) and Hematocrit value (Ht) was recorded in the groups of fish exposed to UVA comparing to the control groups. Such decrease was significantly (p<0.05) increased with the increasing of exposure time. The exposure to different doses of UVA induced marked red cell shrinkage (increased Mean Cell Hemoglobin Concentration (MCHC)) and showed an elevation in Mean Cell Volume (MCV) and Mean Cell Hemoglobin (MCH) in the blood of the exposed fish comparing to the control ones. Concerning to the total White Blood Cell count (WBCs), a significant (p<0.05) reduction was recorded in the blood of exposed fish comparing to the control. The biochemical parameters (blood glucose, total plasma protein, blood cholesterol, plasma creatinine, Aspartic Amino Transferase (AST) and Alanine Amino Transferase (ALT) exhibited a significant increase in the blood of fish exposed to different doses of UVA. The groups exposed to UVA subjected to the Nicronuclei (MN) and Binuclei (BN) tests showed a statistically significant increase (p<0.05) of MN and BN frequencies with the increasing of exposure time. In conclusion, the results confirmed the sublethal effect of UVA on C. gariepinus by using a set of hematological and biochemical parameters. The recorded changes in the hematological and biochemical parameters and the formation of MN and BN in the blood of the exposed fishes revealed the hematotoxic and genotoxic effect of UVA. The selected biochemical parameters could be effectively used as potential biomarkers of UVA toxicity to the freshwater fish in the field of environmental biomonitoring and they could be ranked as possible biomarkers of pollution. It is concluded that the fishes can effectively used as monitors of water quality with respect to radiation.