Calophyllum inophyllum L. (Calophyllaceae), locally called "tamanu" in French Polynesia, is an evergreen pantropical tree growing mostly along the seashores. Its barks, leaves, and fruits are still used in traditional medicine. The oil expressed from the nuts has been also traditionally used. Tamanu oil is topically applied on skins as well as mucous membrane lesions. This oil is especially recommended to heal all kinds of skin ailments. Bioassays and different assessments of Tamanu oil revealed numerous biological activities (antioxidant, anti-inflammatory, antibacterial, wound healing...), so bringing scientific evidence of beneficial effects of this oil on human skin healing. Such biological properties may explain the use of tamanu oil as an active cosmetic ingredient recorded as "Calophyllum inophyllum seed oil" by the INCI (International Nomenclature of Cosmetic Ingredients). Most of the bioactive properties of tamanu oil are attributed to oil composition including the presence of resinous compounds in tamanu oil beside common fatty acids, which constitutes a unique characteristic of this healing oil. Actually, resinous part of tamanu oil is known to contain bioactive secondary metabolites mostly constituted by neoflavonoids including pyranocoumarin derivatives. Herein, chemical constituents and biological properties of tamanu oil are presented with a focus of its traditional use inspiring modern valuations related to cosmetic field.