Abstract: The past decade has seen an increase in application of Raman spectroscopy in composite science. Messages used from this powerful method of structure characterization, however, are toalarge extentlimited to the linear variation of certain Raman frequency shifts with stress level in high perfo rmance fibers suchas carbon and aramid. In this paper, results of Raman spect roscopic studies on these fibers and their model composites are reviewed emphasizing their importance to the under standing of interfacial stress transfer mechanisms. Experimental aspects of applying Raman spectroscopy in inter facial stress measurement, interfacial structure characterization and residual stress measur ementare discussed systematically with examples. It is suggested that correct know ledge of Raman scattering processes from composites is the most important factor for further application of the technique in composite science.