A simple isocratic high performance liquid chromatograph (HPLC) system is described to perform a rapid separation, identification and quantitative determination of vitamin E (alpha-tocopherol) in biological membranes. It makes use of a reverse phase C18 column with pure methanol as the mobile phase, and an ultraviolet detector which enables its quantification in the nanogram scale. This procedure was applied to lipid extracts from whole muscle homogenate and from a preparation of sarcoplasmic reticulum vesicles from skeletal muscle, where the vitamin E contents was determined.