Objective To review generation, distribution of microRNA-203 (miR-203) and it’s relation with tumors. Method Domestic and international literatures were collected to summarize the generation, distribution of miR-203 and it’s relation with tumors. Result Although the previous studies of miR-203 have shown an encouraging result, but only a small portion of miR-203 biological functions are identified, the regulatory mechanism of downstream target genes also has not been fully elucidated. Conclusion With deepening of research, miR-203 might play an active role in classification, categorizing, diagnosis, treatment, and prognosis of tumors.