In grinding, it is required to clarify the processing phenomenon and the process to be made intelligent. The acquisition of detailed tool information is necessary for the purposes. Consequently, not a small number of measurements for wheel working face has been reported. This measurement is expected to be high-speed and performed on the machine. However, there is no measuring system, which is suitable for these purposes. Therefore, this paper describes a high-speed 3-D measuring system for wheel working face on the machine. In this system, a sensing head similar to a laser displacement meter is used. The sensing head is attached to grinding head by two automatic stages. The wheel rotating at 30m/s peripheral speed is scanned by these stages. The scanning resolution is 3μm for X, Y, and Z respectively. This system essentially does not have any limitation for the measurement area. The results of measurements are studied experimentally. As a result, the data obtained by this system is in good agreement with that by a laser microscope.