We assessed the changes in olfaction and mucociliary transport after functional endoscopic sinus surgery (FESS) in 80 patients with chronic paranasal sinusitis. Olfaction was evaluated with the butanol threshold test and mucociliary transport was assessed by saccharin transit time (STT). Postoperative butanol threshold scores were significantly reduced (p < 0.01), and the changes were more profound in severer forms of paranasal sinusitis as graded by ostiomeatal-unit computed tomography. The mean preoperative STT (27 min) which was significantly longer than that of controls (12 min) was significantly reduced 1, 6 and 12 months following FESS (p < 0.01). The results suggest that impairment of olfaction and mucociliary transport in chronic paranasal sinusitis may be significantly improved following FESS.