Circular RNA‐synaptosome associated protein 47 (circ‐SNAP47; Hsa_circ_0016760) is oncogenic in non‐small‐cell lung cancer (NSCLC); however, its role is undescribed in cis‐diamminedichloroplatinum II (DDP) resistance. We attempted to investigate its expression, role and mechanism in DDP‐tolerant NSCLC. As a result, circ‐SNAP47 expression was upregulated in human DDP‐tolerant NSCLC tissues and cells, accompanied with WEE1 G2 checkpoint kinase (WEE1) upregulation and microRNA (miR)‐625‐5p downregulation. Functionally, interfering circ‐SNAP47 and/or restoring miR‐625‐5p curbed the 50% inhibitory concentration of DDP, colony formation, cell proliferation and invasion, accompanied with apoptotic rate promotion and depressions of multidrug resistance (MDR) markers MDR1 and MRP1, anti‐apoptosis protein Bcl‐2, and pro‐invasion protein MMP9. Notably, circ‐SNAP47 interference suppressed xenograft tumor growth of DDP‐tolerant NSCLC cells by elevating miR‐625‐5p and descending WEE1. Mechanistically, circ‐SNAP47 directly targeted miR‐625‐5p, and miR‐625‐5p further targeted WEE1. Therefore, circ‐SNAP47‐miR‐625‐5p‐WEE1 axis might participate in chemoresistance and progression of DDP‐tolerant NSCLC.