Objective：To investigate the significances of fecal calprotectin（FC） in the differential diagnosis of common intestinal dis－eases including inflammatory bowel disease（IBD），irritable bowel syndrome（IBS） and colon cancer. Methods：A total of 120 fresh fecal samples were collected from the out-patients and were divided into health control，IBS，IBD and colon cancer groups（n=30）. ELISA was used to quantitatively determine the levels of fecal calprotectin in each group and sensitivity and specificity of the calprotectin diagnosis of IBD and colon cancer，which were compared with traditional inflammation indicators including erythrocyte sedimentation rate（ESR），C reactive protein（CRP） and white blood cell count（WBC）. Results：There were statistically significant dif－ferences in levels of fecal calprotectin between IBD group and colon cancer，IBS and healthy control groups（P<0.05）. There were sta－tistically significant differences in levels of fecal calprotectin between colon cancer group and IBS and healthy control groups（P<0.05）. There was no statistical difference in CRP，ESR and WBC levels between colon cancer，IBS and healthy control groups（P >0.05）. There were statistically significant differences in levels of ESR and CRP between IBS and IBD groups（P<0.05）. Sensitivity and specificity of fecal calprotectin diagnosis of IBD were 86.7% and 83.3% respectively，while those of colon cancer were 86.7% and 83.3%. Conclusions：Fecal calprotectin cannot only accurately distinguish intestinal organic disease and functional diseases，but also plays a role in the identification of IBD and colon cancer.