A hair removing agent or a hair growth inhibiting agent is provided by determining an endogenous factor having a hair growth inhibitory activity, screening for substances having an activity similar to that of the endogenous factor or substances enhancing the activity or expression of the endogenous factor, and utilizing the physiological activities of such substances. It has been found that FGF18 inhibits hair growth. A method of screening for FGF18-like active substances, substances that promote the activity of FGF18 or substances that promote the expression of FGF18 to thereby obtain candidates for the hair growth inhibiting agent or hair removing agent is disclosed. Also disclosed is a hair growth inhibiting agent or a hair removing agent comprising, as an active ingredient, FGF18 and/or an FGF18 partial peptide, or an FGF18-like active substance and/or a substance that promotes the activity or expression of FGF18 (e.g., Digenea simplex extract).
