Abstract: Objective To investigate the indicative value of Neutrophils/lymphocyte ratio in the progress of colorectal cancer.Methods Fifty one patients with colorectal cancer,63 cases with adenomatous polyps,75 cases with inflammatory and hyperplastic polyps,48 case of another digestive system tumors and 21case of inflammatory bowel diseases were enrolled in this study in the Affiliated Hefei Hospital of Anhui Medical University.We also chose sixty people as control group whom were conduct enteroscope as physical examination but didn't find any abnormal lesions and compared the date of NLR CEA and CA199 between six groups and different stages of colorectal cancer.The ROC curve was carried out to establish the cut off of NLR and the area under curve(AUC).Furthermore,we compared the diagnostic efficiency of the three tumor markers.Results The level of NLR in patients with colorectal cancer was obviously higher than that of adenoma group,the polyp group,another digestive system tumor group,inflammatory bowel disease group and normal control group(P＜0.05),despite the NLR value in another digestive system tumor and inflammatory bowel disease patients was elevated slightly,while there was no obvious differences between the another groups(P＞0.05).The levels of NLR in patient with Dukes A and B stages were lower than Dukes C and D stages(P＜0.05).The cut off of NLR was 2.73,AUC=0.727,suggesting an accurate diagnostic value.The diagnostic sensitivities of the three markers in order of NLR＞CEA＞CA199,and the specificities in order of CA199＞CEA＞NLR.Moreover,the diagnostic sensitivity and specificity of the combined detections of three markers were higher than either of screening respectively or two indicators of arbitrary joint.Conclusion The elevated value of NLR is corresponding to the high state of inflammation in colorectal cancer,when used NLR as a potential marker for diagnosis of colorectal cancer,the sensitivity is superior to the conventional tumor markers,but the specificity is not high,therefore,we should combined with the other tumor markers to improve the diagnostic accuracy.