Disclosed are a CA-4 antitumour drug, a synthesis method and the use thereof. The CA-4 antitumour drug introduces an alkoxy group or a fluorine-containing alkoxy group at the 4' position of a natural product, i.e., combretastatin, and carries out functional chemical modification at the 3' position thereof. The CA-4 antitumour drug of the present invention has an inhibitory ability for the two targets of tubulin and aryl sulfatase and can be used for antitumour therapy.