Confocal micro-Raman spectroscopy—a valuable analytical tool in biological and medical field of research—allows probing molecular vibrations of samples without external labels or extensive preparation. We employ confocal micro-Raman spectroscopy to characterize renal tumors and normal tissue. Results show that Raman peaks of the renal tumor at 788 and , which belong to and stretching, respectively, have an obvious increase. At the same time, the ratio of in renal tumor tissue is , while that in normal renal tissue is (). This means that more tyrosine conformation transform from “buried” to “exposed” in the presence of cancer. Principal component analysis is used to classify the Raman spectra of renal tumor tissue and normal tissue.