Secondary metabolites of plants origin are the richest source of active therapeutics with. Cissampelos owariensisis (English name: lungworth, Hausa: damaraji, Yoruba: Jokoje and Jenjo: Kinkeh) infusion of rhizomes have been used for treatment of various ailments and maladies. Despite the reports on the medicinal benefits of the plant, there are scanty reports on its toxicity. This study wishes to assess the effects of C. owariensis root bark on some liver parameters in adult albino rats in its attempt to elucidate its toxicity. Four experimental groups of Albino Rats were (control, low medium and high doses) administered with oral doses of 0mg/kg 200mg/kg, 400mg/kg and 600mg/kg per body weight of the methanolic extract dissolved in distilled water respectively. The weights of the animals were monitored over a period of two weeks. The experiment was done in replicates and the data generated analysed using one-way ANOVA using SPSS version 20. The result showed a significant weight gain in the 200mg/kg body weight treatment group, whereas the 400mg/kg and 600mg/kg body weight treatments did not differ significantly to the control. Also, serum AST and ALT levels is not significant when compared to the control group but increasing ALT activity of 15.75±2.50IU to 20.00±3.83IU was observed in the 200mg/kg and 600mg/kg body weight treatment groups respectively. On the other hand, the serum ALP showed significant levels of activities in the higher dose treatment group. The levels of total serum protein in the 600mg/kg bwt and 400mg/kg bwt as significantly lower when compared to the control and 200mg/kg bwt treatment group. There was also significant elevation in levels of total and conjugated bilirubin in the 600mg/kg bwt group compared to the control and 200mg/kg bwt groups. In conclusion, methanolic extract of C. owariensis has no toxic effects on hepatic cell consequent of the normal values of AST and ALT whereas the elevation in ALP and bilirubin in disproportion to ALT and AST could denote a cholestatic pattern of liver toxicity.