The paper introduces the definition of Subject Information Commons (SIC), analyzes the feasibility and necessity of SIC construction in hospital libraries. With the combination of practices in the library of Yantai Yuhuangding Hospital, the working ideas, goals and constructing plans of SIC construction in hospital libraries are put forward. Concrete measures are pointed out in resource construction, space construction as well as the team construction. It provides useful references for traditional information services transforming into subject, specialization, personalization in hospital libraries.