The contents of chlorogenic acid and total flavonoid of Eucommia ulmoides Oliv. spring leaves and autumn leaves of 17 provenances were determined by HPLC and UV spectrophotometer . The chlorogenic acid and total flavonoid contents of spring leav es is 2.31 %～ 4 .59 % and 0.83 %～ 2.69 % respectiv ely .The chlorog enic acid and total flavonoid contents of autumn leaves is 0 .25%～ 2 .02% and 0 .95%～ 2 .01% respectively .As the content of chlorogenic acid of spring leaves is much higher than that of autumn leaves, the no distinctive different content of total flavonoid is in spring and autumn leaves.