DISCUSSION: Lower airway hyperkeratosis is very rare and isolated tracheobronchial involvement has not been documented before. The cause of airway hyperkeratosis is not clear and maybe related with chronic inflammatory stimulus, air pollution, inhalation of poisonous gases, occupational dust exposure or trace element deficiency. The tracheobronchial hyperkeratosis may occur as a result of smoking and chronic dust exposure in this patient who maybe genetically predisposed to such lesions. The relationship between chronic airway infection and hyperkeratosis has not been determined. Does chronic airway infection serve as an incentive for hyperkeratosis? Or loss of normal clean function of airway secondary to hyperkeratosis, induced recurrent infection. Tracheobronchial hyperkeratosis should be differentially diagnosed from bronchial tuberculosis and fungus infection. There is no specific treatment for airway hyperkeratosis yet. The primary concern for the management of airway hyperkeratosis is the potential for malignant conversion. The risk is increased by the presence of dysplasia, since increasing severity of dysplasia appears to increase the risk of malignant conversion. Hence close follow-up with surveillance bronchoscopy is ongoing for this subject.