Objective To summarize progress of imagings and tumor markers in preoperative TN staging of colorectal cancer. Methods The domestic and international published literatures related to application of imagings such as EUS, CT, and MRI and tumor markers such as CEA, CA19-9, and CA-242 in preoperative TN staging of colorectal cancer were collected and reviewed. Results The imagings and tumor markers have different values in the preoperative TN staging of colorectal cancer, but the value of a single application is limited. The combination of imagings and tumor markers could improve the diagnostic accuracy of the preoperative TN staging of colorectal cancer. Conclusion In clinical work, combination of imagings and tumor markers should be selected basing on actual situation of patients so as to improve accuracy of preoperative TN staging of colorectal cancer, and guide clinical treatment and improve prognosis of patients.