Background: Laryngotracheal stenosis as a late complication of prolonged endotracheal intubation is a life-threatening event. In order to determine the related risk factors for this complication, which may vary among different countries, designing a valid questionnaire is necessary. The aim of this study was to select the items and evaluate the face and content validities of a questionnaire developed for assessment of risk factors of post-intubation tracheal stenosis (PITS) in patients admitted in the intensive care unit. Materials and Methods: A mixed method study design was used in four steps in 2015, i.e., 1) a literature review, 2) focus groups with five experts in the field, 3) consultations with intensive care unit (ICU) specialists and thoracic surgeons, and 4) evaluation of content and face validity with 15 experts in a scientific panel using two self-administered questionnaires. Content validity index (CVI) was computed for individual items as well as the overall scale. Results: We extracted the items from different sources of information. An initial version of the 52-item questionnaire was developed and classified into four domains including patient characteristics, intubation features, equipmentdrugs, and complications. The items with an excellent modified kappa were included in the questionnaire. Five questions received more criticism instead of support and were removed (Item-CVI<0.55, fair modified kappa). The ones with an Item-CVI > 0.60 and a good modified kappa were revised, merged, or retained. The new 43-item questionnaire found a scale-level CVI, averaging (Scale-CVI/Ave) of 0.91. Conclusion: The PITS risk factors questionnaire was developed and validated through item selection, expert opinions, and content validity index.