The aim of this paper was to determine the morphotype of Marfan's syndrome based on the examination of three patients affected with this disease. After having described the clinical picture of our patients, we carried out anthropometric measurements with calculation of indexes. This study revealed that patients No. 1 and 2 showed nearly identical morphotypes, while the third case presented an abortive form of Marfan's syndrome with slight signs of hypoandria. The morphotype of Marfan's syndrome can be briefly outlined as follows: excessive height; macroskelia, hypermacroskelia; brachycormia; long upper limbs; arm span exceeding the height; narrow shoulders; narrow and often deformed chest; arachnodactyly of hands and feet; kyphoscoliosis or scoliosis; mesocephaly or brachycephaly; large forehead; leptoprosopic or hyperleptoprosopic face; high arched palate.