Spectroscopy is one of the most widely used technique for estimation of compounds at atomic and molecular level by determining their energy states by studying the light absorbed or emitted when they change states. Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) has emerged as a powerful analytical technique in recent days. This instrument is employed for liquid samples which are atomised and further desolvated, vaporized, atomized, and excited and/or ionized by the plasma. This excited atoms and ions emit their characteristic radiation which is a wavelength adopted for interpretation of concentration information for the analyst. The ICP-OES can measure even trace concentrations of various elements with higher degree of sensitivity and precision even upto PPB level. The drug regulatory bodies are projecting a considerable position in the modern analytical laboratories for routine analysis. The present review highlights the various components of ICP-OES, the advantages of ICP over other analytical techniques for determine metals and a brief literature review on applications of ICP-OES in various fields such as pharmaceuticals, food, environmental, biological, metallurgical, geological and marine applications.