Delayed mucociliary clearance develops the pooling of nasal secretion in the nasal cavity and is a common cause of vicious cycle of symptoms in chronic sinusitis. Mucociliary clearance depends on the ciliary activity, the rheological property of the secretion and on the interaction between cilia and the mucous blanket. Recent reports noted that delayed mucociliary clearane in chronic sinusitis is due to the dissociated interaction between cilia and gel layer rather than ciliary activity. But there are few reports that respectively measured the transport time of gel and sol layers. We measured the transport time of gel layer with vegetable charcoal powder and of sol layers with saccharine solution for the evaluation of the dissociated interaction between cilia and gel layer. The results are as follows : 1) In the control group, the transport time of both layer is within 15 min and increased proportionally. 2) In chronic sinusitis without pooling of nasal secretion, both transport times are within 30 minutes, but show no difference to control groups. 3) In chronic sinusitis with pooling of nasal secretion, the transport time of both layers is dissociated each other. In summary, delayed mucociliary transport time in chronic sinusitis seemed due to dissociated interaction between the cilia and mucus layer.