Abstract: A new, technologically easily feasible process for the preparation of 4(5)-methyl-5(4)-thiomethyl imidazole of the formula ##STR1## and of acid addition salts thereof is described, wherein 4(5)-methyl-5(4)-bromomethyl imidazole hydrobromide is reacted in an aqueous medium at room temperature with potassium O-ethyl dithiocarbonate to the intermediate O-ethyl-S-(4-methylimidazolyl-5-methyl) dithiocarbonate, which is hydrolyzed at the reflux temperature under nitrogen atmosphere with an aqueous HBr or HCl solution to 4(5)-methyl-5(4)-thiomethyl imidazole hydrobromide or hydrochloride resp.The compound is a valuable starting material in the synthesis of cimetidine, a well-known drug in the therapy of the ulcer disease.