The invention discloses a synthetic method for docetaxel. The synthetic method comprises the following steps: 1) dissolving a docetaxel intermediate in glacial acetic acid and adding methanol and water, wherein a mass volume ratio of the docetaxel intermediate to glacial acetic acid is 1: 5-15, a mass volume ratio of methanol to water is 1: 10-20, and a mass volume ratio of glacial acetic acid to methanol is 1: 1-1.5; 2) carrying out a reaction under stirring for 1 to 2 h; 3) adding zinc powder and carrying out a reaction under stirring for 2 to 3 h; 4) carrying out filtering on a product obtained in the step 3) so as to obtain a precipitated solid; and 5) purifying the solid obtained in the step 4 so as to obtain docetaxel. The synthetic method for docetaxel in the invention is simple in synthesis steps and high in production efficiency, and synthesized docetaxel has high purity.