The invention discloses a real-time compensation method for comprehensive errors of a numerical control machine tool. The method comprises the steps that S1, geometrical errors are measured and then identified; S2, a machine tool guide rail thermal error model is established; S3, a Z-direction deviation error model of a machine tool workbench is established; S4, temperature data of positions of the machine tool are collected, and positions of to-be-machined parts are determined; S5, the temperatures of the positions are substituted into the machine tool guide rail thermal error model, and real-time geometrical errors of the machine tool caused by thermal deformation are obtained; S6, the geometrical errors and the real-time geometrical errors obtained in the step S5 are linearly superposed, a G code is changed, and compensation is achieved; S7, the temperatures of the positions and the position information of the to-be-machined parts are substituted into the Z-direction deviation errormodel of the workbench, and real-time Z-direction deviation of the workbench is obtained; and S8, real-time compensation for Z-direction thermal errors of the workbench is achieved by combination with the coordinate origin deviation function. According to the real-time compensation method for the comprehensive errors of the numerical control machine tool, modeling is convenient and economical, the labor needed for experiments can be greatly saved, the shutdown time of the machine tool can be greatly shortened, comprehensive machine tool error information can be provided, and real-time compensation for the comprehensive errors of the numerical control machine tool is achieved.