Abstract: PMBP-loaded polyurethane foam as a extractant for thorium nitrate from aqueous solution is investigated. Open-cell polyurethane foam is proved to be effective as supporting material for chelating extraction agent. Thorium nitrate can be quantitatively extracted by PMBP-loaded polyurethane foam over a wide pH range. The effect of equilibrium time, pH of the solution, thorium concentration, various anions and flow rate on the extraction efficiency of thorium is examined. A technique of extraction chromatography column with PMBP-loaded foam cylinder is developed for trace thorium analysis from bulky water samples.