The primary issue addressed in this research is the Presidential Staff Office's position in the Indonesian constitutional system following the issuance of Presidential Regulation No. 26 of 2015 regarding the Presidential Staff Office. According to Articles 1 to 4 of Presidential Regulation Number 26 of 2015, the Presidential Staff Office's role is to improve the smooth control of national priority programs and to organize presidential political communication as well as to manage strategic issues. This research employs a normative legal methodology. The findings of this study indicate that the Presidential Staff Office (KSP) falls into a category of state organs that are auxiliary/supporting (auxiliary organ state) to the implementation instruments of the primary state institutions (main organ state/constitutional organ), with a hierarchical structure of group/third-tier state institutions that derive their authority from the regulator/establishment under the law or via a Presidential Decree.