A method for preparing the linezolid (compound 1), which comprises the steps of: (1) carrying out the debenzyl reaction of compound 4 in solvent, to obtain the compound 5 or its acetic acid salt; (2) carrying out the acetylation reaction in the amino of the compound 5 or its acetic acid salt obtained in step (1) in solvent to obtain the compound 1. The intermediates to prepare the compound 1 and the acetic acid salt of compound 5. The present preparation method is easy to obtain the chiral materials and the chiral materials are cheap, the process and the post treatment are simple, the intermediate products and the end product are easy to be purified, the total yield is high, their purities are also high, this preparation method is easy to be used in the industry manufacture.