A method for producing an .alpha.,.beta.-unsaturated carboxylic acid ester is provided in which an alcohol (A) is caused to react with an .alpha.,.beta.-unsaturated carboxylic acid or a lower alkyl ester (B) of the .alpha.,.beta.-unsaturated carboxylic acid in the presence of a sulfonic acid group-carrying inorganic porous material (.alpha.), and an .alpha.,.beta.-unsaturated carboxylic acid ester obtained by the above-described method is provided that contains not more than 50 ppm of sulfur atoms based on a weight of the .alpha.,.beta.-unsaturated carboxylic acid ester, not more than 2 mol % of by-product etherification products and not more than 1 mol % of by-product addition products based on the mole number of the .alpha.,.beta.-unsaturated carboxylic acid ester. Such methods are a method for producing an .alpha.,.beta.-unsaturated carboxylic acid ester that does not involve generation of a large amount of waste products and a method for producing a high-purity .alpha.,.beta.-unsaturated carboxylic acid ester that causes only a smaller amount of by-products to be generated, and a high-purity .alpha.,.beta.-unsaturated carboxylic acid ester is provided that contains only a smaller amount of catalyst residues and exhibits less metal corrosion behavior.