Lifetime carbohydrate levels were compared in the laboratory between unfed and honey-fed Microctonus hyperodae (Hymenoptera: Braconidae), a parasitoid of the Argentine stem weevil, Listronotus bonariensis (Coleoptera: Curculionidae). High performance liquid chromatography (HPLC) was used to analyse sugars in individual parasitoids and showed that fed and unfed parasitoids can be distinguished by measuring the total sugar levels. Furthermore, the fructose/total sugar ratio (f/T) of honey-fed M. hyperodae was always higher than that of the unfed individuals. This method should prove very useful for determining the nutritional status of field-collected parasitoids, and for evaluating the benefits gained by parasitoids through the provision of fl oral resources in the field. none