Abstract: Objective To investigate microRNA-21(miR-21) expression in esophageal cancer (EC) and its relationship with clinicopathological features. Methods Expression levels of miR-21 in 72 pairs of EC and adjacent normal tissues were detected by real-time quantitative RT-PCR assay, and the relevance between miR-21 and clinicopathological features was evaluated. Kaplan-Meier and Cox proportional regression analysis were performed to determine the association of miR-21 expression and survival of EC patients. Results miR-21 expression in EC tissues was significantly higher than that in adjacent normal tissues (P=0.001). There was a significant correlation between miR-21 expression and TNM stage, EC progression(P=0.023, P=0.025). In addition, EC patients with higher miR-21 expression had significantly poorer overall survival (P=0.004). Conclusion miR-21 may serve as a potent prognostic marker for tumor recurrence and survival of EC patients, and might be a promising target in the treatment of EC.