As specialized machine tools for manufacturing small-module gears, the dry gear hobbing machines are wildly used in the manufacturing industry. In this study, instead of developing mapping relation between the thermal-induced error and surface temperature change of the dry gear hobbing machine, a new direct measuring method to measure the thermal error was proposed. To quantify its application effect and its advantages over previous methods, a test platform was built and the application effects of three different methods were experimentally assessed. Experiment results showed that, with all of these three methods, the alignment errors of gears can maintain within the ninth level. However from the point of view of minimizing the alignment errors of gears, the direct measuring method seemed to be a better choice since the compensation system adopting this method can maintain the error level less than eighth during a large-volume continuous gear cutting process.