A rapid technique for the determination of solasodine by high performance liquid chromatography (HPLC) following derivatization of the steroidal alkaloid by benzoyl chloride has been developed. In the presence of a 5 M excess of benzoyl chloride, the reaction proceeds to completion in 6 h at 50°C. The levels of benzoylated solasodine can be determined by HPLC at a wavelength of 254 nm, there being a linear relationship between the amount of solasodine injected and the peak area produced. Microgram quantities of solasodine can be detected in this way. The benzoylated product is very stable.