Aim: The current study determined phytochemical constituents evaluated the acute and sub-chronic toxic profiles of Lannea acida methanol leaves extract (LAMLE) in Wistar albino rats Methodology: The phytochemical screening of LAMLE was conducted using standard methods. A total of 31 male albino rats were used for the antioxidant studies. A total of 31 male albino rats were used for the toxicological study. The LD50 was determined using six (6) rats according to OECD, 2001 using fixed limit dose. For the sub-chronic study, the rats were divided into five (5) groups of five (5) rats. Control group (group 1) received distilled water orally 2ml/kg. Groups (2-5) received doses of 250, 500, 1000, 2000 mg/kg of the extracts. The experiment lasted for 28 days. Results: The phytochemical screening revealed the presence of Flavonoids, Phenols, Tannins, Saponins, Alkaloids and Steroids. The LD50 of the extract was found to be greater than 5000mg/kg. There were significant reduction in the concentration of ALT, ALP and ALB (P<.05) in the group that received the highest dose of the extract when compared to the normal control while other liver biomarkers were not significantly different (P>0.05) from the control. The sub-chronic dose of 2000mg/kg of the extracts shows significant (P<.05) decrease in all kidney function biomarkers except chloride when compared to the control. The haematological parameters (WBC, RBC, HGB, Neutruphils) showed a significant decrease in Group 5 when compared to the normal control group while MCV and lymphocytes showed significant decrease (P<.05) when compared to the control. Conclusion: The result suggests that the methanol leaves extracts of Lannea acida is relatively safe and can be used in medicinal formulations.