Provided is a method for simply and accurately measuring sphingomyelin in a sample, and a kit therefor. The method is a method for measuring sphingomyelin in a sample, comprising reacting the sample with a phospholipase D which does not react with sphingomyelin and lysophosphatidylcholine but reacts with phosphatidylcholine, a lysophospholipase or a monoglyceride lipase, and a choline oxidase, eliminating the formed hydrogen peroxide, reacting the resultant with a phospholipase D which does not react with glycerol-3-phosphorylcholine and free fatty acid but reacts with sphingomyelin, and a choline oxidase, and measuring the formed hydrogen peroxide.