Zanthoxylum zanthoxyloides has been used for decades in traditional medicine across West African countries to treat several ailments such as malaria and pain. However, sometimes it is used without information on its toxicity level. This present work aimed to explore the toxicity level of Zanthoxylum zanthoxyloides bark aqueous extract (AZZ) on albino Wistar rats after single and repeated administrations. For the acute toxicity evaluation, a single dose of the extract at 3, 5 and 7.5 g/kg of the extract was administered orally, and the animals were kept under observation for mortality and clinical signs for the first four hours, and then once every day for 14 days. For the sub-acute toxicity evaluation, the extract was administered to the animals orally at doses of 0.5, 0.75 and 1 g/kg daily for 28 days. On the 15 th day (acute evaluation) or 29 th day (sub-acute evaluation), the animals were weighed and anaesthetized and then blood was collected for haematological and biochemical analysis. Vital organs (liver, kidneys and lungs) were removed and weighed. No mortality or toxicological behavior was observed, and there was no statistically significant difference between the treated and control groups for whole body weight and organ weights. Also, the results showed no statistically significant effects on haematological and biochemical parameters. Thus, AZZ may be considered as nontoxic both after single and repeated administrations.