Objective To explore the interfering effect of mucosal evolution on the budesonide treatment for chronic rhinosinusitis with nasal polyps after endoscopic surgery (ESS). Methods 174 cases of type Ⅱ stage 3 and type Ⅲ chronic rhinosinusitis with nasal polyps were randomly divided into experimental group (94 cases) and control group(80 cases). After ESS, budesonide was given to the experimental group (128 μg each side per day), but not to the control group. The comparison of mucosal edema, nasal pus accumulation, sinus meatal window, and epithelia of operation cavity were carried out respectively between two groups. Results 4 weeks later, class Ⅰ in experimental group was 46.8% (44/94), in control group was 30.0% (24/80) (P<0.05); 4 to 12 weeks later, the transfor-marion from class Ⅱ to Ⅰ in experimental group was 90.0% (45/50), in control group was 57.1% (32/56) (P<0.01); 12 weeks later, the total class Ⅰ in experimental group was 94.7% (89/94), in control group was 70.0% (56/80) (P < 0.01). The difference between 2 groups was of statistical significance. Conclusion Emphasizing the importance of integrated treatment after operation, ESS for the patients of sinusitis with nasal polyps was feasible, meanwhile, continuous use budesonide could alleviate mucosal edema, lessen conglutination, accelerate epithelia, and prevent recurrence of nasal polyps.