Objective To investigate the expression levels of serum miR-210and miR-375in patients with non-small cell lung cancer (NSCLC).Methods A total of 25NSCLC patients (NSCLC group) and 14healthy volunteers (control group) were enrolled in this study.The relative expression levels of 9miRNAs (miR-182, miR-126, miR-31, miR-21, miR-221, miR-200b, miR-183, miR-210and miR-375) in 6 NSCLC patients and 6healthy volunteers were measured by RT-qPCR.The dysregulated miRNAs will be selected as candidate miR-NAs.The diagnostic value were evaluated by ROC curve.Results Compared with control group, 2 (miR-210and miR-375) out of 9miRNAs were up-regulated in NSCLC group, and the differences were statistically significant (P＜0.05), while the other 7miRNAs were not consistent with the reported literatures.Therefore, miR-210and miR-375were selected as candidate miRNAs.We found that the relative expression level of miR-210in the lung adenocarcinoma group was significantly different from control group (P＜0.05), while there was no significant difference between the squamous cell carcinoma group and the control group (P＞0.05).There was no significantly statistical difference in the relative expression level of miR-375between lung squamous cell carcinoma group, lung adenocarcinoma group and the control group (P＞0.05).The AUC of serum miR-210of lung adenocarcinoma group was 0.737 5 (95％CI:0.498 3-0.976 7, P=0.091 4) with a medium diagnostic value.Conclusion MiR-210is highly expressed in the serum of patients with lung adenocarcinoma, suggesting that miR-210may be a novel tumor marker for the diagnosis of lung adenocarcinoma.The value of miR-375in the diagnosis of lung cancer still needs to be further explored.