Research The theoretical and practical study of the importance of economic feasibility studies of libraries and their role in maintaining and rationalizing the investment of public or private money in the establishment and management of libraries, thus finding a balance between payments of that money, with what can be expected of the services provided to beneficiaries makes what was spent in the right place of non-waste Or waste, while maintaining the level of performance. This study comes as an Arab input to introduce the economic feasibility of the libraries and experiences of Western countries in this field, with special reference to public libraries in Iraq.