The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway plays a crucial role in regulating immune function and inflammatory responses. Dysregulation of this pathway has been implicated in numerous disorders, including chronic rhinosinusitis with nasal polyps (CRSwNP). However, the potential therapeutic efficacy of targeted JAK inhibition in CRSwNP remains underexplored and requires further investigation.This study aimed to evaluate the efficacy and mechanisms of S-Ruxolitinib, a selective inhibitor of JAK1/2, as a novel therapeutic strategy for CRSwNP.Expression of p-STAT3 and p-STAT6 was analyzed in nasal tissues from CRSwNP patients. A murine model of CRSwNP was established to evaluate S-Ruxolitinib's effects on polyp formation, sinonasal inflammation and epithelial function. Additionally, primary human nasal epithelial cells (HNECs) were cultured to assess S-Ruxolitinib's effects on Th cytokines-induced epithelial dysfunction and production of inflammatory mediators.The expression of p-STAT3 and p-STAT6 was elevated in CRSwNP patients. Intranasal S-Ruxolitinib administration in CRSwNP mice significantly reduced the number of NP-like lesions, epithelial thickness, sinonasal inflammation, disrupted barrier and ciliary integrity, and goblet cell hyperplasia. In vitro, S-Ruxolitinib reversed IL-13-induced epithelial barrier disruption, ciliary dysfunction, and goblet cell hyperplasia. It also inhibited the production of ALOX15, CCL26, and POSTN. Furthermore, S-Ruxolitinib suppressed IFN-γ-induced upregulation of CXCL9, CXCL10, and CXCL11.The findings of this study provide novel evidence that JAK/STAT inhibition using S-Ruxolitinib effectively attenuates sinonasal inflammation and restores mucosal homeostasis in CRSwNP. These results suggest that S-Ruxolitinib holds promise as a potential therapeutic agent for the treatment of CRSwNP.Copyright © 2025. Published by Elsevier Inc.