Cholesteryl nonanoate, also called cholesteryl pelargonate, 3β-cholest-5-en-3-ol nonaoate or cholest-5-ene-3-β-yl nonanoate, is an ester of cholesterol and nonanoic acid.

It is a liquid crystal material forming cholesteric liquid crystals with helical structure.

[1] It is used in some hair colors,[2] make-ups, and some other cosmetic preparations; e.g. the ISP ColorFlow line is based on mixtures with e.g. cholesteryl chloride, cholesteryl oleyl carbonate and BHT.

The mixture provides an opalescent, iridescent appearance.

[3] It is also used in some pleochroic dyes and together with e.g. cholesteryl oleyl carbonate and cholesteryl benzoate in some thermochromic applications.