OBJECTIVE： To investigate clinical efficacy and safety of Budesonide nasal spray in the treatment of chronic rhino-sinusitis complicating with allergic rhinitis after endoscopic sinus surgery. METHODS： 120 patients with chronic rhino-sinusitis complicating with allergic rhinitis were divided into control group and trial group by random number table method， with 60 cases in each group. Both groups received endoscopic sinus surgery. Control group received normnl saline for nasal cavity lavage after 1 week of surgery； trial group received Budesonide nasal spray， morning and night， one week after surgery. Both groups received treatment for 3 months. Allergic rhinitis-related symptom score before and 3 months after treatment and clinical efficacies were compared between 2 groups. The ultrastructure of nasal mucosa was observed using light microscope and electron microscope. The incidence of ADR was analyzed statistically. RESULTS： Before treatment， there was no statistical significance in allergic rhinitis symptom score between 2 groups （P＞0.05）； after treatment， allergic rhinitis symptom score of 2 groups were decreased significantly， and the trial group was significantly lower than the control group， with statistical significance （P＜0.05）. Total effective rate of trial group was 94.83％， which was significantly higher than 50.00％ of control group， with statistical significance （P＜0.05）. The nasal mucosa pathologic glands and edema of 2 groups were improved significantly， with statistical significance （P＜0.05）； there was no statistical significance between 2 groups （P＞0.05）. The time of nasal mucosa recovery in trial group （3 months） was significantly shorter than in control group （6 months）， with statistical significance （P＜0.05）. There was no significant difference in the incidence of ADR between 2 groups （P＞0.05）.CONCLUSIONS： Budesonide nasal spray in the treatment of chronic rhino-sinusitis complicating with allergic rhinitis after endoscopic sinus surgery shows significant therapeutic efficacy， and can significantly improve allergic rhinitis-related symptom and recovery ultrastructure of nasal mucosa with good safety.