The balance between human body composition, e.g. bones, muscles, and fat, is a major and basic indicator of personal health. This paper proposes a new discrimination method for measuring the thickness of subcutaneous fat and muscular layers based on tissue elasticity. The validity of the proposed method was evaluated in twenty-one subjects (twelve women, ten men; aged 20-70 yr) at three anatomical sites. Experimental results show that the proposed method can achieve considerably high discrimination performance.