Recently, the policies and management of public libraries have been evaluated by the Ministry of Public Administration and Security, the Ministry of Culture, Sports and Tourism of the central government, and Gyeonggi Province in Korea. However, these evaluations do not meet the international trends where simple input-output measures are being overtaken by outcomes calculating broad socio-economic values. Taking these facts into consideration, the main goal of this paper is to analyze the limitations of the recent library evaluation cases and to suggest some desirable directions for the evaluation of the socio-economic values (i.e., impact and benefits) of public libraries.