Sugar phosphates and nucleotides in an extract from leaves kept under steady-state photosynthetic conditions were separated on an anion-exchange resin (Shodex TML) column with a programmed gradient elution by borate—phosphate buffer and quantitated within 3 h. The effluent mixed with orcinol—sulphuric acid reagent was introduced into a reaction tube and irradiated with UV light. The resulting coloured carbohydrates from sugar phosphates and nucleotides could be very sensitively determined with a spectrophotometer. Sample preparation for chromatography was simple and the recovery of standard compounds added during extraction procedures was quantitative.