Colorectal cancer (CRC) is a common digestive tract tumor for which surgical resection is mainstay of treatment, or in combination with chemotherapy and radiotherapy. At present, the treatment mode has evolved from the traditional "group-based" diagnosis and treatment to the precise "individualized" therapy. Precision medicine is to find the cause of the disease and the therapeutic targets through genome detection, and finally forms a diagnosis and treatment system involving the screening of cancer-related molecular markers, accurate diagnosis and classification, and precise treatment with the help of cancer genome sequencing and information analysis. Whole exome sequencing (WES) is a new gene sequencing technique, which has been widely applied in the fields of complex human diseases and various malignant tumors. Some progress has also been achieved in its application in studies concerning the pathogenesis, treatment, metastasis risk assessment and prognosis estimation of CRC.