The science of government and the constitutional law are two different sciences based on their own ontology,epistimology and axiology. However, they can not be stand alone at the level of implementation. This articlemainly focus on how the intertwine, position, and differences among those two sciences.This article was written based on a normative research which mainly used secondary data. Literature studyused as its tool and data collection method. After being collected, the data were analized by using descriptivequalitative method.So, the science of government cannot be separated from the constitutional law and even the constitutionallaw cannot run alone without the science of goverment. Only in their ontology, epistemology and axiology,the two sciences can be distinguished concretely, but at the level of implementation, they are united.