AbstractThe composition of technical cashew nutshell liquid (CNSL), Anacardium occidentale, from four different sources has been examined. The C15 component phenols cardanol, cardol, 2‐methyl cardol, and traces of anacardic acid have been determined by gas liquid chromatography (GLC), after hydrogenation and methylation, on the stationary phases Dexsil 300, SE52, SE30, and OV17, or alternatively the acetylated (unsaturated) phenols on Dexsil 300, SE52, or SE30. After thin layer chromatographic (TLC) separation of the component phenols, their saturated (15:0), monoene (15:1), diene (15:2), and triene (15:3) constituents have been determined by mass spectrometry (MS). In both the GLC and the MS procedures, the results have been corrected for differing relative responses. The more highly polymeric material present in technical CNSL from different sources has been determined by molecular distillation and by TLC. The fractions obtained by molecular distillation have been analyzed by GLC, the results of which show there is present some low polymeric material less volatile than the C15 component phenols, but the major portion of technical CNSL is volatile and can be analyzed by GLC.