In summary, our data demonstrate that: i) miR-23a is frequently downregulated in the radioresistant NPC tissues, and its decrement significantly correlates with NPC radioresistance, and is an independent predictor for the poor survival of NPC patients; ii) upregulation of miR-23a increases NPC cell radiosensitivity both in vitro and in vivo; iii) reduced miR-23a increases NPC radioresistance through activating IL-8/Stat3 signaling. Here, STAT3 is linked to nasopharyngeal carcinoma.