PURPOSE: A pharmaceutical composition containing Lysimachiae Foenum-Graeci Herba fraction or foenumoside for preventing and treating obesity or diabetes is provided to enhance glucose absorption and to suppress adipcyte differentiation. CONSTITUTION: A pharmaceutical composition for preventing and treating obesity contains foenumoside A of chemical formula 1, foenumoside B of chemical formula 2, foenumoside C of chemical formula 3, foenumoside D of chemical formula 4, or foenumoside E of chemical formula 5 as an active ingredient. The composition is a capsule, tablet, granule, powder or beverage. A therapeutic agent for preventing and treating obesity contains the pharmaceutical composition as an active ingredient. A method for preparing Lysimachiae Foenum-Graeci Herba fraction comprises: a step of adding a solvent selected from water, low alcohol of C1-4 or mixture thereof to Lysimachiae Foenum-Graeci Herba to obtain a crude extract； a step of adding water to the crude extract and fractioning with hexane, chloroform, ethyl acetate and n-butanol to obtain n-butanol soluble fraction； a step of isolating by adsorption column chromatography to obtain a first fraction； a step of isolating the first fraction by fast protein liquid chromatography(FPLC) to obtains a second fraction； and a step of isolating and purifying the second fraction by preparative liquid chromatography to obtain foenumoside A, B, C, D, and E.본 발명은 영릉향 분획물 또는 포에뉴모사이드를 유효성분으로 포함하는 비만 또는 당뇨병 예방 및 치료용 약학 조성물에 관한 것으로, 더욱 상세하게는 지방세포분화를 저해하고 포도당 흡수를 증가시킬 수 있는 영릉향 분획물 또는 포에뉴모사이드 A, 포에뉴모사이드 B, 포에뉴모사이드 C, 포에뉴모사이드 D 및 포에뉴모사이드 E로 구성되는 군으로부터 선택되는 1 이상을 유효성분으로 포함하는 비만 또는 당뇨병 예방 및 치료용 약학 조성물, 기능성 식품, 화장료 조성물에 관한 것이다.
