[Problem] Provision of a composition for external use on skin that is safe to use and has an anti-inflammatory and anti-allergic actions. [Solution] A composition for external use on skin in the treatment of inflammatory disease which comprises dihomo-γ-linolenic acid (DGLA) as an active ingredient. The DGLA is preferably contained as a glyceride, a phospholipid, or an alkyl ester. The composition for external use contains DGLA in an amount of 0.1-50 wt%.