Machining compensation method of electric spark machine tool

The invention discloses a machining compensation method of an electric discharge machine tool, which comprises the steps of judging whether a temperature difference value is not less than a preset value or not and selecting a corresponding compensation mode according to a judgment result, and the step is operated in a machining process: if the temperature difference value is not less than the preset value, calculating a lead screw variation through the temperature difference value and a lead screw temperature curve; the lead screw variable quantity distribution is added into the lead screw pitch compensation table, and the lead screw pitch compensation table added with the lead screw variable quantity is used for compensation; and if the temperature difference value is smaller than the preset value, the numerical control system directly reads the screw pitch compensation table for compensation. By the adoption of the scheme, a reasonable compensation mode can be selected according to the temperature differenc