The invention discloses a method for preparing a loxilan intermediate. 5-nitro-N-(2-hydroxyethyl)-m-formamide benzoic acid serving as an initial raw material is subjected to methyl esterification reaction with methanol, amidation reaction with 3-amino-1,2-propylene glycol in methanol solution, iodination reaction with iodine monochlorde in aqueous solution after the product of amidation reaction is reduced with ferric acid, acetylation reaction with acetic anhydride and hydrolysis in aqueous ammonia to obtain 5-acetamido-N-(2,3-dihydroxypropyl)-N-(2-hydroxyethyl)-2,4,6-triiodo-1,3-phthalic amide. The target compound can be obtained by acylation and hydrolysis reaction after the iodination reaction; the use of the expensive iodine monochlorde is avoided at the initial stage of the reactionsteps, so the cost of the whole reaction is greatly reduced; and the reaction condition is mild and the purity of the product is high because the aqueous ammonia is used in the hydrolysis reaction.