Introduction: Lipedema is an abnormal deposit of subcutaneous fat most often involving the lower limbs symmetrically. The physiopathology is poorly understood, but its peak of the almost exclusively female involvement and its peak of appearance at puberty, during pregnancy or at menopause orient toward a hormonal involvement, whereas other elements are in favor of a strong genetic predisposition. Klinefelter syndrome (KS) is a genetic disease linked to aneuploidy resulting in a karyotype 47 XXY most of the time. There is a substantial variation in clinical presentation, but it often features infertility, firm testicular hypotrophy, hypergonadotropic hypogonadism, gynecomastia, and learning difficulties. Many other pathologies are associated with KS, but lipedema is never mentioned and there are no data in the literature linking these two pathologies. Observation: We report the cases of a 55-year-old man (146.8 kg, body mass index [BMI] 40.96 kg/m 2 ) whose diagnosis of KS was known when hospitalized for lipedema, and of a 62-year-old man (198.1 kg, BMI 68.55 kg/m 2 ) whose diagnosis of KS was made after the hospitalization for lipedema. Discussion: The concomitant presence of these two rare pathologies encourages the construction of an epidemiological study to support this association. It is also an element that can feed the research on the physiopathology of these two affections. Finally, the clinician must know how to suspect the possibility of lipedema in a patient with KS presenting an enlargement of the lower limbs and should know how to evoke a diagnosis of KS in front of a lipedema aspect in a man.