Circular RNAs (circRNAs) are functional RNAs in the development and metabolism of non-small cell lung cancer (NSCLC). Therein, this paper particularly elucidated the circRNA SEC61 subunit alpha isoform 1 (circSEC61A1) in NSCLC has not been fully elucidated.Clinical analysis of circSEC61A1 expression was performed on specimens collected from 51 patients with primary NSCLC, together with patients' survival. Cell experiments were performed after interfering with circSEC61A1, microRNA (miR)-513a-5p, and peroxisomal biogenesis factor 5 (PEX5) expression, respectively, and cell malignant phenotypes and aerobic glycolysis were evaluated, as well as epithelial-to-mesenchymal transition (EMT)-related markers and Wnt/β-catenin pathway. Xenografts experiments studied the performance of circSEC61A1 in vivo. The downstream molecules of circSEC61A1 were searched. Our data demonstrated that circSEC61A1 was upregulated in NSCLC patients, showing an association with poorer survival outcomes. In cell experiments, cir-cSEC61A1 overexpression promoted NSCLC malignant phenotypes, glycolysis, EMT, and Wnt/β-catenin pathway activation, whereas circSEC61A1 underexpression did the opposite. Knockdown of circSEC61A1 limited tumor growth and metastasis. Furthermore, circSEC61A1 could regulate PEX5 expression through competitive absorption of miR-513a-5p. Generally, circSEC61A1 is a potential biomarker for NSCLC, and cir-cSEC61A1 serves tumor-promoting action in the progression of NSCLC.