AbstractChlorogenic and quinic acids were isolated from the kernel of sunflower seed by column chromatography and identified by paper chromatography. Ultra‐violet and infra‐red spectra of the above acids were compared with those of pure preparations. The contents of both acids in the kernel and hull of sunflower seeds were determined and the conversion of chlorogenic acid into quinic acid at temperatures of 100° and 135° was followed. During storage of sunflower meal re‐synthesis of chlorogenic acid was observed. Effects of isolates of chlorogenic and quinic acids on α‐amylase, trypsin and lipase activity were detected.