With increasing interest in content marketing, SNS (social networking services) has become more popular as a method of library marketing, both at home and abroad. Accordingly, this study analyzed the operational status and problems of library SNS marketing, in an attempt to find ways to optimize its use. Results show that librarians’ opinions of library marketing and library SNS marketing were very high, but the problems they faced included a lack of human resources dedicated to marketing, lack of marketing education, a lack of content to upload each week, and low numbers of contacts on social networking sites. To further develop and optimize library SNS marketing, five solutions were suggested based on the survey results: first, composing an intensive managing team for effective SNS operation; second, providing different levels of marketing training to decrease the librarians’ mistakes; third, updating data continuously; fourth, providing information and services users need; and lastly, clearly identifying each channel’s active operation goals.