【Abstract】 Objective To explore the causes of failure of functional endoscopic sinus surgery (FESS) and/or septoplasty, and the clinical effect of modified functional rhinoplasty. Methods From January 2013 to December 2017, 40 patients with chronic rhinosinusitis (CRS) with or without deviation of the nasal septum who underwent functional endoscopic sinus surgery and / or septoplasty were collected. The clinical data were analyzed retrospectively. The symptoms and causes of failure of functional endoscopic sinus surgery and / or septoplasty were evaluated by CT, VAS and Lund Kennedy score, respectively. According to the cause of the disease, the modified reconstruction of nasal function was performed, including lobular rhinoplasty, columella rhinoplasty, crooked nose correction, flap area rhinoplasty, modified septum rhinoplasty, and modified functional endoscopic sinus surgery. Lund Kennedy score and VAS were used to evaluate the clinical effect of modified rhinoplasty. Results The reasons for failure of functional endoscopic sinus surgery include: 38 cases (95%) of frontal recess stenosis, 34 cases (85%) of air chamber residue of ethmoid sinus in anterior group, 31 cases (77.5%) of air chamber residue of ethmoid sinus in posterior group, 37 cases (92.5%) of maxillary sinus stenosis, 26 cases (54.2%) of sphenoid sinus stenosis, 34 cases (85%) of uncinate process residual, 34 cases (85%) of middle turbinate deformity and 11 cases (27.5%) of dislocation of nasal septum. The reasons for the failure of correction of deviation of nasal septum include: 20 cases (50%) of deviation of cartilage of nasal septum, 18 cases (45%) of deviation of vertical plate of ethmoid bone, 10 cases (25%) of deviation of nasal spine of palatine bone and 14 cases (35%) of deviation of vomer bone. The reasons for the failure of the operation were as follows: 2 cases (5%) of cartilaginous rhinoconus, 2 cases (5%) of bony rhinoconus, 1 case (2.5%) of columella and 2 cases (5%) of lobular deformity. After 6 months of followup, there were significant differences in VAS score and Lund Kennedy score (P＜0.05). There were 39 cases of complete control, 1 case of partial control and 0 case of no control. The total effective rate was 975%. Conclusion The main reason for the failure of functional endoscopy and / or septoplasty in patients with nasosinusitis is the residual of the abnormal anatomical structure of the complex of the sinus, the frontal recess and the caudal end of the nasal septum. The modified reconstruction of nasal function can effectively treat the patients with chronic nasosinusitis with or without septal deviation.