The invention relates to a high-content 2-methyl allyl chloride preparation method. A chlorination reaction solution obtained through the reaction of isobutene and chlorine is taken as the raw material, the high-content 2-methyl allyl chloride is obtained through continuous rectifying of an isobutyl chloride separation tower, an isobutylene chloride separation tower and a 2-methyl allyl chloride separation tower, wherein the separation of isobutylene chloride uses a extractive distillation method. The preparation method has the advantages that the number of needed rectifying towers is small, the content of the obtained 2-methyl allyl chloride is high, and the energy consumption is low.