PROBLEM TO BE SOLVED: To provide a novel anti-inflammatory agent which suppresses an inflammatory reaction, containing a rare fatty acid. An anti-inflammatory agent containing the following fatty acids: (1) a C18 fatty acid having a hydroxyl group or a carbonyl group at the 10-position, (2) a C18 fatty acid having a hydroxyl group or a carbonyl group at the 13-position, (3) a C18 or C20 fatty acid having a hydroxyl group or a carbonyl group at the 12th position, (4) a C20 fatty acid having a hydroxyl group or a carbonyl group at the 15th position, or (5) a hydroxyl group or a carbonyl group at the 10th position. A fatty acid having 16 carbon atoms. [Selection diagram] None【課題】希少脂肪酸を含む、炎症反応を抑制する新規な抗炎症剤を提供する。【解決手段】以下の脂肪酸を含む、抗炎症剤:(1)10位に水酸基またはカルボニル基を有する炭素数18の脂肪酸、(2)13位に水酸基またはカルボニル基を有する炭素数18の脂肪酸、(3)12位に水酸基またはカルボニル基を有する炭素数18または20の脂肪酸、(4)15位に水酸基またはカルボニル基を有する炭素数20の脂肪酸、または(5)10位に水酸基またはカルボニル基を有する炭素数16の脂肪酸。【選択図】なし