Abstract: AIM: To simultaneously analyze the chemical components existing in the caterpillar body and stroma of Cordyceps sinensis, especially nucleosides and ergosterol, and compare the performances of several solvents used to extract nucleoside components. METHODS: To carry out qualitative and quantitative analysis by means of HPLC-DAD detection, heuristic evolving latent projections (HELP) resolution method and overall volume integration method. RESULTS: Peak purity examination and the resolution of overlapping peaks in chromatogram could be conducted by HELP method upon the two-way data and so the pure chromatogram and spectrum of each component were obtained. The recoveries were between 99.97% and 100.81%, the distributions of nucleoside components existing in caterpillar body and stroma were quite different. The performance of distilled water to extract nucleosides was the best. CONCLUSION: In comparsion with the classic one wavelength chromatography, much better qualitative and quantitative results could be obtained by HPLC-DAD and HELP resolution method.