Next, a mixture of the prenol type (polyprenol) and dolichol 多萜醇type (dihydropolyprenol) was subjected to analysis using this capillary HPLC system, and each homologue was separated successfully. During analysis of the polyprenol fraction derived from Eucommia ulmoides leaves, in addition to the all-trans-polyprenol and cis-polyprenol that were previously identified, dolichols were observed as a single peak. This high-resolution and sensitive system is very useful for the analysis of compounds that are structurally similar to polyprenols and dolichols and have small amounts of these alcohols.