【Abstract】 Objective To study the upper airway mucosal inflammatory pattern, and evaluate associations between bacterial colonization in CRS of Tibetan patients. Methods Nasal sample tissue was obtained from 75 Tibetan CRS patients（40 CRSwNP, 35 CRSwNP）and 30 control subjects during endonasal sinus surgery or septoplasty. Samples were processed for assessment of proinflammatory cytokines and mediators by immunoassay. Prior to surgery nasal swabs were taken from each patient for microbiological evaluation. Results CRSsNPs were characterized by significantly high levels of IFNγ and IL17 Than other groups (P≤005）, which slightly increased of IL8 and IL1β compared with that of the control. CRSwNPs were characterized by increased mediator promoting eosinophilic inflammation IL5, ECP and a predominance of eosinophils and mast cells (P≤005). Conclusion In highaltitude, the dwelling Tibetans of CRS presents a Th2 milieu with eosinophilic inflammatory reaction and associated with Gram- bacterial load in CRSwNPs, otherwise, Th1 and Th17 presents polarization with reaction of neutrophils inflammation and associated with Gram+ colonizing in CRSsNPs.