The chip removal process in grinding is characterized by intensive friction and plastic deformation leading to the risk of thermal damage of the surface-layer of the machined part. Thus productive and reliable grinding processes need effective monitoring. The difficult to access contact zone between the grinding wheel and the workpiece led to extensive research work on the temperature measurement in the grinding arc. In order to develop a tool integrated temperature monitoring system a new approach was undertaken which makes use of the measurement of infrared-radiation to monitor the temperatures in the grinding arc. The presented research work shows promising results suitable for an industrial applicable system for temperature measurement in grinding. The optical transmission of the infrared temperature information in combination with a fast detecting infrared sensor bares the potential to establish a highly miniaturized measuring system which is easy to integrate in any grinding wheel at comparably low production costs.