Abstract: 
In last few years Raman spectroscopy becomes essential analytical technique in various department of science. Because of technological advancement in instrumentation of Raman spectroscopy they became alternative technique for other invasive techniques for analysis. Raman spectroscopy is non-invasive, minimal sensitive to water, based on inelastic scattering of monochromatic light. Raman spectra is obtained by sample is subjecting to the laser source radiation, electron within the sample interact with radiation leads to light scattering. This review describes principle and instrumentation of Raman spectroscopy along with its pharmaceutical application. Raman spectroscopy has different applications including chemical imaging, identification and quantification of drugs, polymorphs, inorganics and minerals, In-process monitoring, medical diagnostic, analysis of drug abuse, analysis of turbid sample and also in novel drug delivery system. Advantages like minimal training to operate, simple in operating, accurate and no or minimal sample is required to analyse have made Raman spectroscopy is an charming analytical tool.

Keywords: Raman Spectroscopy, Surface Enhanced Raman, Spectroscopy, Pharmaceutical Application.