Sex hormones are divided into androgen and estrogen, which can directly or indirectly regulate the activity of sebaceous glands. Among them, testosterone (T) and dihydrotestosterone (DHT) are most biologically active in androgens. After binding to androgen receptor in the basal layer of sebocytes, the excessive increment and sebum production of sebum cells are promoted by synergistic action with PPAR ligands. 1,2 However, estrogen does not directly affect the activity of sebocytes, but can achieve indirect effects by inhibiting androgen regulation of sebocytes. 3 For example, progesterone can block androgen receptors and inhibit the activity of free androgen in vivo. Estradiol can reduce the level of androgens with bio-active by up-regulating the level of sex hormone-binding globulin. 4 Therefore, sex hormones do have a crucial effect on sebocytes. Importantly, we also supported this by qualitative analysis in the changes of skin surface lipid (SSL) content and composition in people with different sex hormone levels through lipidomics.Lipidomics can conduct a comprehensive and systematic analysis of lipids, reveal the relationship between lipids and cells, organs, and bodies in physiology and pathology by identifying the structure and function of lipids. 5 In the past few years, we used lipidomics (Ultra Performance Liquid Chromatography-Quadrupole Time-of-Flight-Mass Spectrometer, UPLC-QTOF-MS) to analyze the important role of lipids in different skin conditions. [6][7][8][9][10] Including acne vulgaris, sensitive muscles, etc., we found significant differences in SSL in different skin conditions. [10][11][12] Importantly, when we studied the SSL of young men and women and middle-pregnancy women (without obvious skin diseases), we stumbled upon potential consistency in their lipid changes. Through literature research and data analysis, we found that this phenomenon may be related to the level of sex hormones in the body. 13 The regulation of sebocytes by sex hormones leads to the change of sebum. 14 Therefore, this paper focuses on sex hormones and sebum, in order to reveal the important association of sex hormones on sebum.