Background/Aims: This study aimed to determine the dynamic change of postoperative T-helper cell cytokines in nasal secretions and serum in chronic rhinosinusitis with nasal polyps (CRSwNP). Methods: Nasal secretions and serum samples of 30 CRSwNP patients and 10 healthy subjects were collected. Among CRSwNP patients, samples of 30 patients were collected 1 day before endoscopic sinus surgery (ESS) and that of 18 patients (12 asthmatic and 6 non-asthmatic) were collected 4, 8, and 12 weeks after ESS. Concentrations of interleukin (IL)-2, IL-4, IL-5, IL-17, and interferon gamma (IFN-gamma) were determined by Cytometric Beads Array. The Sino-Nasal Outcomes Test 22 and Lund-Kennedy endoscopic scoring (LKES) system were collected for all patients. Results: The levels of IL-2 and IL-5 in secretions of CRSwNP were significantly higher than that of healthy control at the baseline. At the 4th and 8th week after ESS, the IL-4 levels in nasal secretions of the asthmatic group were significantly higher than their baseline controls (preoperatively). From the 4th to 12th week after ESS, the IL-2, IFN-gamma, IL-4, and IL-17 levels in nasal secretions of the non-asthmatic group were significantly increased as compared to their baseline controls. Postoperative IL-5 levels in serum of the asthmatic group decreased significantly as compared to their baseline controls. There was no significant association between LKES and levels of cytokines in postoperative secretions and serum. Conclusions: Our results indicate that postoperative endoscopic findings may not directly reflect the underlying mucosal inflammation, and surgery could not change the systemic immunity status. Despite endoscopic resolution of mucosal abnormalities, it may not avert the need for subsequent postoperative medical intervention to treat the underlying mucosal inflammation.