Aim: The objective of this study was to investigate the ameliorating effect of a natural bentonite found in Nigeria on liver enzymes of Wistar rat fed with cyanide from cassava waste water. The enzymes assayed were alkaline Phosphatase (ALP), alanine amino transferase (ALT) and aspartate amino transferase (AST). Materials and Methods: A total of 45 Wistar rats were used. The rats were divided into four groups and a control group. Each group had nine rats including the control. Groups 1, 2, 3, and 4 were given a daily dose of 0.4ml of cassava waste water containing a sub-lethal amount of cyanide (2.16 x 10-3 mg) for three weeks. Groups 2, 3, and 4 were counter administered with 0.2 ml, 0.4 ml, and 0.8 ml of 7% bentonite solution respectively. Administration of bentonite was done simultaneously with the cyanide administration. Serum samples were assayed weekly for ALP, ALT and AST activities.