To establish the quantitative analysis method for adenosine and cordycepin in Cordyceps sinensis by HPLC. The sample was extracted with pure water under ultrasonic for 40 min. After centrifugation and filtration, the extract was analyzed by HPLC with C18 column at 1.0 mL/min and detected at 260 nm wavelength. The mobile phase was composed of pure water and methanol(85:15, V/V) and the column temperature was 30℃ . This method showed the LOD was 0.2 μg/mL, LOQ was 1.0 μg/mL. The average recoveries of adenosine and cordycepin were 94%- 103% and RSD bellow 3% . The method had high sensitivity, selectivity and simple operation, and can be used for testing the adenosine and cordycepin.