The feasibility of discriminating atrophic gastritis and gastric cancer from healthy controls and gastric cancer after operation by serum based on Raman spectroscopy was explored. Fifteen atrophic gastritis, 16 gastric cancer, 12 gastric cancer after operation and 14 controls were selected in our experiment. Comparison between different Raman spectra demonstrated that there are changes occurred with the deterioration of diseases. Three parameters were calculated and compared among groups. This exploratory study demonstrated potential for developing serum Raman spectroscopy analysis into clinical use for gastric diseases.