The authors remind some essential notions on Hashimoto's thyroiditis, and sum up the recent data on the physiopathology of the main auto-immune thyroid disturbances. One case of Hashimoto's thyroiditis diagnosed through out atypical ophthalmological symptoms, leads the authors to formulate different hypothesis integrating all the elements of this case in a single nosographical system, following a review of the literature on thyroid ophthalmopathy.