The recent advances in nanoscience and nanotechnology have greatly facilitated the development of nanoparticle drug delivery system. A nanoparticle drug delivery system of silymarin will improve its poor solubility in water and oil, thus enhancing its bioavailability. A variety of nanoparticle formulations of silymarin such as solid lipid nanoparticles, microemulsion and selfemulsifying drug delivery system, and liposomes have been extensively investigated. This paper reviews the advances of these formulations on their preparation and characterization, absorption and bioavailability, as well as in vivo and in vitro studies, in order to provide an assessment of current research for further pharmaceutical studies of silymarin. © 2011 Journal of Chinese Pharmaceutical Sciences, School of Pharmaceutical Sciences, Peking University.