The invention relates to a method for comprehensively utilizing carbon dioxide and waste plastics. The method comprises the steps: adopting the waste plastics as raw materials, introducing gaseous CO2 and hydrogen, promoting melting and cracking of the waste plastics, then carrying out liquefying and catalytic reaction under the condition that a catalyst exists, and preparing gasoline and diesel with high additional values. The method improves the utilization value of the waste plastics, simultaneously can carry out carbon fixation, and reduce the pollution caused by greenhouse gases for the environment, and the finished gasoline and the finished diesel which are produced can be directly used as fuel oil.