Micro-Raman spectroscopy was employed to identify gastritis tissues and gastric ulcer tissues. The primary spectral differences between the two types of samples include, for gastric ulcer tissues, (1) the intensity of the peak at 781 cm(-1) ascribed to cytosine decreases, while the peaks ascribed to adenine and thymine respectively at 793 and 823 cm(-1) become stronger; (2) the bands of amide I and amide III at 1654 and 1320-1270 cm(-1) respectively, characteristic of alpha-helix structural protein, lose their intensities, and the tryptophan band at 1332 cm(-1) and phenylalanine band at 1003 cm(-1) reduced significantly, while the tryptophan marker at 1554 cm(-1) up shiftes to 1556 cm(-1) with increasing intensity; (3) a blue shift of 1073 cm(-1) line, the characteristic Raman band of lipid, and a reduction in the ratio of 1303 cm(-1) assigned to in-phase CH2 twisting motion to 1268 cm(-1) from =CH in-plane deformation were observed; (4) statistic analysis shows that the ratio of Raman intensities at bands 1449 cm(-1) originating from CH2 group to 1660 cm(-1) from amide I provides a promising standard to distinguish the two tissues.