This research is basically designed to ascertain and analyze the various problems of federalism and Nation-building in Nigeria. This work will adopt the use of secondary source of data as the main method of data collection. Certain literature, which seem to be relevant to the study were consulted and reviewed adequately. To ensure reliability, some hypotheses were posited and there are first, the problems facing Nigeria federalism and nation-building. Another is the nature of prolonged military rule in Nigeria. Finally, appropriate measures for nation-building to empower federal structure in the future. It is clear that any nation which is not united or nationally build through fiscal federal system or federalism will not achieve any good set objectives that will be based on common of its citizenry. So the issue of this study is to identify and solve those problems that hinders nation-building through the introduction of fiscal federalism in Nigeria. The hypotheses were validated. With those problems of federalism and nation-building still hanging on, a very precarious situation and this nation will definitely destroy its citizenry and keep them disintegrated and thereby defeating the rationale behind the adoption of fiscal federalism in Nigeria.