The objective of the present work was the microbiological analysis of laryngeal and tracheal mucosal swabs as well as the study of the contents of the tracheostomy tubes taken from the patients presenting with laryngeal and tracheal stenosis of different etiology. Both the in- and outpatients with different duration of the cannula-bearing period were involved. Special attention was given to the influence of the tracheal stents and the frequency of their cleaning on the microbiocenoses of the larynx and trachea. The study has demonstrated that the patients bearing cannulas are in need of everyday toilet of the tracheostomy tube and tracheostoma; also needed is the choice of the tubes with due regard for a the anatomical features along with general and local antibacterial therapy for reducing pathogenicity of microflora in the tracheobronchial tree and decreasing the frequency of postoperative complications.