Abstract: An illuminating device for machining tools is disclosed. A machining tool is installed with an illuminating device that uses a single LED prepared using the multi chip single module technique to provide high-power light. This elongates the lifetime of the illuminating device and has the advantages of power-saving and low temperature. The light thus produced does not have UV and IR components. In addition to no radiation injury to human bodies, the invention also avoids overlapped shadows in the case of multiple LED sources. Such a design of the cold and single light source can effectively bad influences on the precision of objects 31 being processed.