We have achieved click-free visualization of the alkyne-tagged cell proliferation probe EdU by means of Raman microscopy. To our knowledge, his is the first example of direct imaging of an alkyne-modified molecule in living cells. The results demonstrate the potential of the alkyne moiety as an excellent Raman tag for live-cell imaging of small molecules. At least in the case of EdU, the ethynyl group is small enough not to affect the biological activity of the parent small molecule, and this result indicates that click-free imaging using Raman microscopy has the potential to be a powerful methodology for chemical biology research. It should be mentioned that the imaging speed of our approach could be further improved by application of nonlinear Raman techniques such as coherent anti-Stokes Raman scattering (CARS) and stimulated Raman scattering (SRS) microscopy. These efforts are just beginning, and Raman imaging of other small, alkyne-tagged molecules as well as the development of improved instrumentation is under way.