The purpose of this national study is to identify the factors affecting the public library use among the Korean adult population. The study constructed a model of three types of factors to explain the frequency of public library visits: an individual's socio-demographic characteristics, input and output measures of the local library, and the community size and library investment of the local government. The data were collected from both a national representative sample of 1,000 adults of 18 years old or above who participated in a web survey and the 2013 National Library Statistics of Korea. It was found that a more frequent public library visit occurred when a person who read more and lived closer to the library, which was newly established in a small to medium-sized scale, who lives in a city with a greater population and with more library staff members serving a fewer patrons. Implications for future public library constructions and for public services were suggested based on the study findings.