BACKGROUND: Selenium (Se) is an essential dietary mineral and Radix puerariae (RP) (the dried root of Pueraria lobata Willd.) is a botanical supplement widely used as a nutraceutical. Food enriched with Se provides a feasible and economic approach for production of organic Se compounds. However, little is known about Se-enriched RP and the structure of Se-containing polysaccharides and proteins derived from Se-enriched RP. RESULTS: The organic form of Se accounted for 82.42% of total content. Purification by DEAE-52 and Sephadex G-100 column chromatography yielded three single fractions-RP-SeP-11, RP-SeP-22 and RP-SeP-33-with Se contents of 0.9562×10-3, 0.6113×10-3 and 0.3827×10-3 g kg-1, respectively. RP-SeP-11 (3.5 kDa) was made of glucose, RP-SeP-22 (19.6 kDa) was composed of xylose and glucose, and RP-SeP-33 (97.9 kDa) was made up galactose, mannose and glucose. Two Se-containing proteins were obtained with Se content of 3.175×10-3 and 4.328×10-3 g kg-1, respectively. One appeared as three subunits with molecular masses of 43.0, 29.0 and17.8 kDa while the other appeared as two subunits with molecular masses of 43.0 and 26.3 kDa. CONCLUSION: The results provide a basis for promoting the utilisation of RP resources enriched with Se as a promising tool for the food industry and are significant for its contribution to Se biochemistry in plants. © 2013 Society of Chemical Industry.