||The main difficulties of brake disc infrared temperature measurements are the unknown of disc surface emissivity, non-uniform and time-varying, and the high rotation speed and deceleration of the disc, which makes it difficult to follow the special distribution of the temperature. To provide information on the emissivity variation during braking, brake disc temperature and emissivity were investigated by an original optic-fiber two-color pyrometer combined with an infrared camera, which allows monitoring the true friction areas. In addition, an optical top-tour was used to identify disc revolutions. The evolutions of the surface temperature and emissivity on successive disc revolutions were successfully determined. It was showed that circumferential thermal gradients form on the surface and maintain their angular position, they can, however, win or lose in intensity with braking progress.