Abstract: The omnimedia has spawned more interconnected, more convenient and more diverse reading needs, which has put forward urgent requirements for transforming the service concept and reading promotion mode of public libraries. This paper takes the practice of the visual identity system upgrade of Shanghai Library as an example, and discusses the feasibility of conveying the transformational strategy of the library to the public by shaping a brand-new institutional image. Practice shows that the upgrading of visual identity system is an effective way for public libraries to integrate into the omnimedia era, and also a feasible way to build a new transformational institutional image based on own characteristics and development concepts.