We estimate the reheating temperature of the universe after Gauss-Bonnet (GB) inflation by using the primordial gravitational wave (PGW). Inflationary tensor power spectrum has a blue tilt ($n_T > 0$) for the selected model of inflation; hence, the energy spectrum of the PGW significantly enhances. As a result, the PGW spectrum induced by GB inflation is detectable by future concepts of GW detectors. We further perform analyses on the reheating parameters including the temperature, the equation of state, and the number of e-folds. Our results imply that the Gauss-Bonnet term plays an important role not only during inflation but also during reheating whether the process is instantaneous or lasts for a certain number of e-folds until it thermalizes and eventually completes. This presentation is based on our previous works [2].