as an important part of national digital library (ndl), the national digital library project (ndlp), which was launched in 2005, has attracted wide attention of the society in general. this paper introduces the general situation of the project from the follow-ing aspects, namely, the characteristics, objectives and contents. it also expounds on the basic ideas and the overall structure of the project and gives an introduction to the design of its basic platform, its application platform, its business management system and its standardization control system. in this paper, the digital resources construction and service delivery of the national library of china (nlc) are introduced to cover both its present operation as well as those in conjunction with the opening of its new library building during its second-phase of library development. finally, the most important and dif.cult point in the construction of the national digital library project is analyzed from the following four perspectives: 1) the long-term preservation of digital resources; 2) the construction of knowledge organization system; 3) the organic integration of the digital library and the traditional library; and 4) the risk of project management and system integration.