MicroRNA-223 (miR-223) is located on chromosome X, and is highly conserved in the process of evolution. In recent years, many studies have shown that miR-223 is abnormally expressed in a variety of digestive system tumors, such as esophageal cancer, gastric cancer, liver cancer, pancreatic cancer and colorectal cancer. MiR-223 can participate in the proliferation, apoptosis and invasion of tumor cells through a variety of signal pathways, which is expected to become a marker for the diagnosis and prognosis of digestive system tumors.