A multi-functional cutting tool can be used for a turning process as well as a drilling process. The multi-functional cutting tool includes: a shank having a flat surface to be fixed to a cutting device; first and second cutting portions of cylindrical shape, each of which extends from the respective ends of the shank; and a cooling hole straightly extending and penetrating into the cutting tool from the end of the first cutting portion to the end of the second cutting portion in a direction of the rotational axis of the cutting tool.