Digital humanities, which is the combination of modern information technology and traditional humanities research method,has been regarded as a hot topic in recent years. As the resource preservation and service centers for humanities research, libraries are experiencing the shift from resources management and document search services to data management and knowledge services. With the support of semantic web, big data, artificial intelligence and other new technologies, plus the methods of knowledge reorganization in the Internet Age,the digital humanities projects of libraries are dedicated to providing knowledge services which are different from traditional document search services. Taking the" Celebrities Manuscript Archives" of Shanghai Library as an example, and with reference to the theory and practice of other digital humanities projects, this paper summarizes the construction process of library digital humanities projects from the aspects of methods,work flow and technical framework.