Purpose: To investigate the antioxidant properties, the inhibition of selected enzyme activities of ultrasonication-assisted mango seed kernel extract (MSKE), and to evaluate the physical stability and skin irritation properties of a cosmetic cream formulated with MSKE. Methods: Choke-Anan MSKE and a Kaew cultivar of Thai mangoes were prepared by ultrasonication-assisted extraction. Antioxidant activities (DPPH, FRAP, H 2 O 2 scavenging assay, ABTS), antityrosinase, anti 5-lipoxygenase, antihyaluronidase and anti α-glucosidase were determined. Cosmetic creams containing 0, 1, 2 and 3 % of MSKE were prepared and evaluated for physical stability. The most stable formulation was subjected to the clinical skin irritation test. Results: The yield, total polyphenol content, antioxidant properties and inhibition of 5- lipoxygenase, hyaluronidase and α-glucosidase were higher (p 0.05) in tyrosinase inhibition activity compared to arbutin. However, a slightly lower α-glucosidase inhibition activity than acarbose was observed. The cosmetic cream containing 1 % Choke-Anan MSKE had good physical stability with no skin irritation. Conclusion: MSKE exhibits good antioxidant and enzyme inhibitory activity. Thus, it is a potentially natural functional ingredient for use in food and cosmetic industries. Keywords: Mango, Antioxidant, Enzyme inhibitory activities, Cosmetic product stability, Skin irritation