BACKGROUND: Bronchiolitis is a distressing respiratory condition and the most common cause of hospitalization during the first year of life. The hospitalization of an infant is a stressful event for parents and deserves careful consideration. The objective of this work was to develop and validate a self-administered instrument that comprehensively assesses the impact on parents of the hospitalization of their infant for bronchiolitis. METHODS: The Impact of Bronchiolitis Hospitalization Questionnaire (IBHQ©) was developed using a literature review and pre-study interviews with both parents and clinicians. For finalization and psychometric validation, it was included in a multicenter, longitudinal, observational study conducted in France. Parents of infants under the age of 1 year and hospitalized for bronchiolitis were asked to complete the questionnaire at hospital discharge, and 3 months after. RESULTS: Seven hundred and seven questionnaires were completed by the parents of the 463 eligible infants. After finalization, based on principal component analyses, the IBHQ included 30 core items allowing the calculation of 7 dimension core scores (Worries and distress; Fear for future; Guilt; Impact on daily organization; Physical impact; Impact on behavior with hospitalized infant; Financial impact), as well as 16 optional items, allowing the calculation of 5 optional dimension scores (Disturbed breastfeeding; Physical reaction of hospitalized infant; Impact on feeding; Impact on behavior with other infants; Siblings' reaction). Internal consistency reliability and construct validity of the IBHQ were satisfactory. The highest impact was observed for "Worries and distress", "Fear for future" and "Impact on daily organization" scores. CONCLUSIONS: The IBHQ is a reliable and valid instrument for assessing the multifaceted impact on parents of the hospitalization of their infant for bronchiolitis.