Despite several decades intensive efforts,the development of accurate protein force fields remains as a major challenge.[1] There are two key issues:(1) How to obtain intrinsic conformational potentials of each amino acid residue;(2) How to effectively incorporate these conformational potentials into a force field.[2] We have developed novel strategies to address the above two issues.Namely,intrinsic conformational potentials can be obtained by the statistical analysis of protein coil library,[3] and these conformational features can be effectively incorporated into a force field by using residue specific torsional functions.