The effect of oral daily administration for twenty eight (28) days of stem bark aqueous extract of Khaya senegalensis on alkaline phosphatase (ALP), aspartate aminotranferase (AST), alanine aminotransferase (ALT) activities and on the level of serum total bilirubin and total protein were investigated using Albino rats in three dose levels (10, 20, and 40 mg/kg body weight) plus a group serving as control. The result obtained indicated significant (p<0.05) increase in ALT, AST, ALP, and total bilirubin level in comparison with control. However, significant (p<0.05) decrease was
observed in the level of total protein in comparison to control. The result indicated that the aqueous stem bark extract of Khaya senegalensis may possess toxic potential, at the dose levels studied.