Rosai-Dorfman disease is a non-Langherans cell histiocytosis typically revealed by lymphadenopathy. Extranodal involvement occurs in 43% and most commonly involves the head and neck, skin, and bones. Few reports have described laryngeal lesions. We report the case of a Rosai-Dorfman disease in a 27-year-old female, presenting as an obstructing transglottic mass. We provide the results of the MRI and PET-scanner examination. As the treatment relies on surgical excision and the diagnosis depends on pathological examination, we also detail the analysis results that followed the surgical resection. This report highlights the necessity to consider Rosai-Dorfman disease as a potential diagnosis in case of a laryngeal submucosal mass.