The serum level of Cyfra21-1 was always elevated in patients with nonsmall cell lung carcinoma. The aim of this meta-analysis was to evaluate the serum Cyfra21-1 as a biomarker in the diagnosis of nonsmall cell lung cancer (NSCLC).All the articles associated with serum Cyfra21-1 in the diagnosis of NSCLC were searched in the PubMed, Medline, and CNKI databases. The number of patients for true positive, false positive, false negative and true negative were extracted from each individual study. The pooled sensitivity, specificity, positive likely hood ratio (+lr), negative likely hood ratio (-lr), diagnosis odds ratio (dor) and summary receiver operating characteristic (sroc) curve were calculated by MetaDiSc 1.4 software.After searching the databases, 17 studies with 4221 subjects were met the inclusion criteria and finally included in this meta-analysis. The pooled diagnosis sensitivity, specificity, +lr, -lr and dor were 0.72 (95% confidence interval [CI]: 0.70-0.73), 0.94 (95%CI: 0.93-0.95), 8.81 (95%CI: 6.36-12.22), 0.42 (95%CI: 0.32-0.55) and 22.57 (95%CI: 13.89-36.68) respectively. The area under the sroc curve was 0.95. And significant publication bias was found in this meta-analysis (P = 0.049).With published data, the serum Cyfra21-1 was a useful biomarker for diagnosis of NSCLC.The serum level of Cyfra21-1 was always elevated in patients with nonsmall cell lung carcinoma. The aim of this meta-analysis was to evaluate the serum Cyfra21-1 as a biomarker in the diagnosis of nonsmall cell lung cancer (NSCLC).All the articles associated with serum Cyfra21-1 in the diagnosis of NSCLC were searched in the PubMed, Medline, and CNKI databases. The number of patients for true positive, false positive, false negative and true negative were extracted from each individual study. The pooled sensitivity, specificity, positive likely hood ratio (+lr), negative likely hood ratio (-lr), diagnosis odds ratio (dor) and summary receiver operating characteristic (sroc) curve were calculated by MetaDiSc 1.4 software.After searching the databases, 17 studies with 4221 subjects were met the inclusion criteria and finally included in this meta-analysis. The pooled diagnosis sensitivity, specificity, +lr, -lr and dor were 0.72 (95% confidence interval [CI]: 0.70-0.73), 0.94 (95%CI: 0.93-0.95), 8.81 (95%CI: 6.36-12.22), 0.42 (95%CI: 0.32-0.55) and 22.57 (95%CI: 13.89-36.68) respectively. The area under the sroc curve was 0.95. And significant publication bias was found in this meta-analysis (P = 0.049).With published data, the serum Cyfra21-1 was a useful biomarker for diagnosis of NSCLC.