The present study investigated the effects of sublethal concentrations of dichlorvos on liver marker enzymes (aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase), acid phosphatase (ACP), serum total protein (STP), bilirubin, urea and creatinine in African Catfish (Clarias gariepinus) juveniles at sub acute period under laboratory conditions. A total of 90 juveniles of Clarias gariepinus with average weight and length of 200.15 ± 0.09g and 26.00 ± 0.00cm respectively were kept in three experimental groups of 30 per group in triplicate of 10 fishes. Groups 1 and 2 were exposed to dichlorvos at dosages of 21 and 43mg/l respectively and group 3 served as control for 15 experimental days. Analyses were carried out on days 1, 5, 10 and 15. From the results, there was no significant changes in the biochemical parameters tested on day 1 of the experiment but levels of the liver enzymes, ACP and bilirubin increased significantly (p<0.05) on other experimental days when compared with the control group. However, there was insignificant increase in the urea level and also a non-significant decrease in the creatinine and Serum total protein (STP) levels of the experimental groups when compared with the control group. From the analyses and observations made, we conclude that the administration of sublethal concentrations of dichlorvos to African catfish induced some damages to the liver which affected the levels of the liver enzymes and the increase in ACP level is indicative of carcinogenicity.