OBJECTIVE To investigate the efficacy of the treatment of endoscopic sinus surgery on patients dignosed as chronic sinusitis with nasal polyps(CRSwNP) complicated and asthma. METHOD Data of 45 patients with CRSwNP complicated asthma were analyzed retrospectively. RESULT All cases were followed up for a period of 1 to 3 years after operation. In the 45 cases treated with ESS, 32 cases were cured, 9 cases were improved and 4 cases were inefficient by the treatment. The cure rate was 91.1% (41/45). The asthma symptoms were improved in 16 patients compared to 4 before the surgery. CONCLUSION With ESS based on combined therapy,it can significantly improve the condition of CRSwNP, asthma symptoms and pulmonary function. Meanwhile, sufficient perioperative period preparation should be made to ensure the safety of the operation.