ObjectiveTo detect the changes of mir34b expression in nasopharyngeal carcinoma (NPC) and explore its clinicopathological significance.MethodsSpecimens from 114 NPC patients hospitalized in our department from Jan 2016 to Oct 2017 were included and 40 benign nasopharyngeal specimens obtained during endoscopic surgery of nasal polyps were selected as control. Fluoroscence quantitative polymerase chain reaction (PCR) was used to detect the expression of miR34b. The relationship between the mir34b expression and clinicopathological features of NPC was analyzed.ResultsThe２△Ｃt value of miR34b in the NPC group was 0.136±0.021, which was lower than that of 0.294±0.052 in the control group (P<0.01). The２△Ｃt value of miR34b was insignificantly correlated with patients' gender, age and differentiation of tumor (all P>0.05). The ２△Ｃt value of miR34b in NPC specimens of stage Ⅲ and Ⅳ was 0.126±0.015, which was lower than that of 0.183±0.046 in those of stageⅠand Ⅱ (P<0.05). And the value in lymph node metastasis subgroup of NPC was 0.116±0.013, which was lower than that of 0.162±0.041 in subgroup without lymph node metastasis (P<0.05).ConclusionLow expression of miR34b is detected in NPC, which may participate in the occurrence, development, and lymph node metastasis of this tumor.