The complex morphology and structures of biomaterials in biological systems have attracted chemists and material scientists to understand self- assembly mechanisms of their emergence. The growth of biomaterials is strongly influenced by soluble biopolymer, low mass organic molecules in solution, and insoluble tissue around crystals. Mimicking the nature, various polymers with different functionalities and their combinations of these functionalities have been designed or adopted in order to control the morphology and complexity of inorganic crystals. In addition, natural polymers or modified functional polymers with specific functional groups have also been used for such mimicking process. In this review, the latest development of synthetic/natural polymer directed crystal growth and mediated self-assembly of nanoparticles will be overviewed. Soluble polymers including biopolymers and synthetic polymers as soft templates have shown remarkable effects on the directed crystal growth and controlled self-assembly of inorganic nanoparticles. The flexible combinations of these soluble polymers with other additives or reaction systems make it possible for access of various inorganic materials with complex form, taking advantages of the synergistic effects of polymer with other low mass organic molecules or reaction environments. In contrast, insoluble polymers with different functionalities can be used as hard templates or substrates to offer suitable crystallization sites for the guided crystallization and self-assembly processes. Recent advances have demonstrated that polymer directed crystal growth and mediated self-assembly of nanoparticles can provide promising ways for rational design of various ordered inorganic and inorganic-organic hybrid materials with complexity and structural speciality. Biography: Shu-Hong Yu studied Chemistry and got his B.Sc. degree in 1988 at Hefei University of Technology, and completed his Ph.D. in Inorganic Chemistry in 1998 from the University of Science and Technology of China under the supervision of Prof. Yi-Tai Qian. He worked as a JSPS research fellow from 1999 to 2001 with Prof. Masahiro Yoshimura in the Materials and Structures Laboratory at the Tokyo Institute of Technology. He was subsequently an Alexander von Humboldt research fellow at the Max Planck Institute of Colloids and Interfaces in Potsdam, Germany, working with Dr. Helmut Cölfen and Prof. Markus Antonietti. Since 2002, he has been a full professor and is leading the Division of Nanomaterials and Chemistry at Hefei National Laboratory for Physical Sciences at the Microscale at the University of Science and Technology of China. He was jointly nominated as the Group Leader of the Partner Program of the Max Planck Society (MPG) and the Chinese Academy of Sciences (CAS) in 2005. He has authored and co-authored more than 95 refereed journal publications, six invited book chapters, and two patents. He also serves on the editorial board for Current Nanoscience, and Chinese Journal of Inorganic Chemistry. His research focuses on bio-inspired self-assembly strategies, biomimetics, and novel mild chemical routes for the rational design of new nanostructured modular materials, as well as their related properties and applications. Shao-Feng Chen was born in Anhui, China, in 1979. He obtained his Bachelor degree in the Department of Materials Science and Engineering at the Kunming University of Science and Technology in 2002. He is currently focusing on biomimetic synthesis of nanostructured materials under the supervision of Prof. Shu-Hong Yu for pursuing a M.S degree in the Department of Materials Science and Engineering at the University of Science and Technology of China.