Objective To develop a rat model of rhinogenic chronic rhinosinusitis (CRS) and observe biological characteristics during succession of inflammation. Methods Animals (n=48) that underwent unilateral maxillary sinus ostial obstruction using Merocel nasal packing with standard staphylococcus aureus inoculation were examined for blood routine examination before operation and at 3 days, 4, 8 and 12 weeks after operation. Following sacrifice at 3 days, 4, 8 and 12 weeks, the obtained maxillary sinuses were prepared for histologic investigation and bacterial culture. Experimental interventions were compared with normal controls (n=12) and with contralateral control sinuses within each animal.Results White blood cell counts (WBC) at 3 days, 4,and 8 weeks were significant higher than that of controls (P<0.01), and the peak was in 4 weeks, while WBC at 12 weeks descended to the normal (P>0.05). Perforation of nasal septum, was observed in 95.7% of the animals (44/46), within 3 days, which almost located in anteroinferior of the nasal septum. Anatomical and histologic characteristics of chronic sinonasal inflammation were gradually present and stable from 4 to 12 weeks. The similar inflammation happened in the contralateral control sinuses within each animal as compared with the experimental sinuses. Standard staphylococcus aureus was detected in 36.4% of bilateral sinuses at 4 weeks, while none at 12 weeks but conditional pathogenic bacterium in 66.7% of bilateral sinuses. Conclusion Unilateral maxillary sinus ostial obstruction using Merocel nasal packing with standard staphylococcus aureus inoculation results in a persistent, stable CRS in rat until 12 weeks after operation, when further investigations into disease pathophysiology would be appropriate. No more evidence demonstrates that infection contributes to the persistence and stability of inflammation of CRS.