With the growing interest in the 4th industrial revolution and big data, various policies are being developed for facilitating the use of public open big data, which are leading to a wide range of added values created from use of such data. Despite the expanded requirements for public data disclosure and the legal system improvement, however, the use of public open big data is still limited. According to the literature review, there are studies on policy proposals for the government guiding directions for public open big data, but there is a lack of studies that handle the issue from the users' viewpoint. Therefore, this study aims to analyze the public open data ecosystem in Korea and to analyze public open big data through interviews with the providers (the government and public institutions) and users (private sector companies and citizens). This way, the study finds inhibition factors and facilitation factors, draws out issues and suggests solutions through a causal relationship analysis between each factor. Being a research on finding measures for facilitating both public big data release and use, this study has theoretical implications. In the meanwhile, the derived issues and alternatives provide practical implications also for stakeholders who are planning to facilitate release and use of public open big data.