A method for preparing a rosuvastatin calcium intermediate, including a) contacting a halogenated ethene with magnesium metal to obtain a halogenated ethene Grignard reagent, and carrying out a Grignard reaction between the halogenated ethene Grignard reagent and R-epichlorohydrin; b) adding sodium cyanide for carrying out a nucleophilic substitution reaction; c) adding alcohol for carrying out an alcoholysis reaction; d) adding a basic solvent for carrying out protection of a first hydroxyl group; e) selectively oxidizing a second hydroxyl group; and f) adding triphenylphosphine in alkaline condition for carrying out a Wittig reaction.