According to the data released by the National Cancer Center in 2019, the morbidity and mortality of colorectal cancer in China are on the rise. This mainly related to the lack of basic medical treatment standards, and the overall level of diagnosis and treatment is still low. Especially in county-level hospitals, due to the relatively backward allocation of various resources, it is impossible to completely follow the international treatment guidelines, and the medical level is uneven. Since county-level hospitals are the first unit of treatment for most patients with colorectal cancer, and the number of people who need services is large, it is especially important to develop guidelines for colorectal cancer diagnosis and treatment suitable for county-level hospitals. To this end, Professional Committee of Internal Medicine, Colorectal Cancer Committee of Chinese Medical Doctor Association drafted, discussed, and finally released Guidelines Internal Medicine Section for county physicians in diagnosis and treatment of stageⅡ and Ⅲ colorectal cancer in China, to standardize stage Ⅱ and Ⅲ colorectal cancer medical treatment.