Laryngeal carcinoma (LC) is one of the common human cancer types. MicroRNAs (miRNAs) were reported to be the essential regulators in cancer diagnosis, treatment, and prognosis. It was reported that miR-206 expression was reduced in various neoplastic diseases. However, the role and functional mechanism of miR-206 in LC progression remain unclear. In this research, miR-206 was found to be associated with tumor-node-metastasis (TNM) staging. In addition, the area under the curve (AUC) of miR-206 was 0.902 for diagnosis of LC and 0.854 for differential diagnosis of stage I-II and stage III-IV patients. Low expression of miR-206 was associated with poor prognosis of LC patients. miR-206 expression was an independent factor affecting the prognosis of LC patients, as revealed by the Cox regression analysis. In vitro experiments demonstrated that miR-206 overexpression reduced cell multiplication, invasion, and migration and increased cell apoptosis in LC cells. Moreover, SOX9 was a target of miR-206, and miR-206 negatively regulated SOX9 expression. Collectively, miR-206 might be a promising biomarker with diagnostic and prognostic value for LC, and the miR-206/SOX9 axis might be a candidate target for LC therapy.