Abstract: Colorectal cancer (CRC) is one of the common malignant tumors worldwide and the fourth most common cancer in China.In recent years the incidence of CRC is still on the rise.It is of great significance to carry out effective screening for CRC with regard to improving prognosis and reducing mortality.Among many screening methods currently available,the detection of tumor markers in feces and serum is easy to operate,inexpensive,and noninvasive,thus becoming the focus of research.In view of the great significance of tumor marker detection for CRC screening,this article discusses the value of four protein tumor markers in CRC screening,with an aim to provide a theoretical basis for their clinical use.