Diabetes mellitus is a metabolic disease characterized by abnormally high glucose level in blood. Plant-based compounds are now being studied as alternatives for diabetes. Due to limited information on the pharmacologic activity of Musa acuminata, also known as “lakatan”, this study was carried out to determine the effect of Musa acuminata aqueous leaf extract on blood glucose level of alloxan-induced diabetes mice and to assess its safety in vivo. Thirty male ICR mice (Mus musculus) were divided into six groups (n=5) and were administered intraperitoneally with alloxan monohydrate (75 mg/kg) (5 groups), or normal saline solution (sham control group). Treatment groups were given distilled water (both sham and negative control groups), glimepiride (17.6 μg/kg, positive control), or one of the three doses of M. acuminata leaf aqueous extract tested (250, 500 and 1000 mg/kg) concomitantly via oral gavage for 28 days. The blood glucose levels of the mice were measured at baseline and at 0th, 14th and 28th. Phytochemicals present as well as signs of general toxicity were also determined. Results showed that M. acuminata (1000 mg/kg) significantly decreased blood glucose level (P<0.05) and has comparable activity with that of the positive control. Phytochemical analysis revealed the presence of tannins, cardiac glycosides, alkaloids, steroids and terpenoids. Also, there were no changes in behavior and activity observed in mice treated with M. acuminata. These observations strongly suggest that the M. acuminata leaf extracts has blood glucose lowering properties and is safe for consumption.