Nonsmall cell lung cancer (NSCLC) is greatly affected by the dysregulation of the immune system. Circulating follicular helper T cells (Tfh) play critical roles in inducing B-cell activation and producing various cytokines. In the current study, we investigated levels of circulating Tfh in NSCLC. Circulating Tfh and it subtypes were determined by measuring CD3, CD4, CXCR5, CXCR3, and CCR6 in 62 NSCLC patients and 66 healthy controls using flow cytometry. Data presented that percentage of circulating Tfh in the peripheral CD4(+) T cells was significantly increased in NSCLC (14.0%) than in controls (8.7%) (p<0.001). Further analysis revealed that the upregulation of Tfh was contributed by the Th2-Tfh subtype and the Th17-Tfh subtype, whereas the percentage of the Th1-Tfh subtype was significantly decreased in patients. Investigating the clinical stages of the patients demonstrated that prevalence of Tfh was significantly elevated in cases with advanced stages (III: 14.2%; IV: 16.4%) than those with primary stages (I: 10.9%; II: 10.8%). In addition, we analyzed Tfh in patients with different histological types. Results showed that the percentage of circulating Tfh was further upregulated in adenocarcima than squamous cell carcinoma or other types. This study suggests the involvement of circulating Tfh in the pathogenesis and progression of NSCLC, and provides a potential pathway for understanding this disease.