The amendments through Indonesian Constitution of i945 (UUD I945) have impacted to various change including to government system. The change an the government system has came about UUD 1945 (at pre-amendments) is the semi-presidential then it's become hilly presidential system after amended. The -author here also scrutinizes on the government system which had appeared in not only the constitutional level but also on the practice in the national implementations. The author also presents her advices for the legislator members to deeper grasped toward basic concepts which had been exercised by UUD l 945 post-amendments, including the presidential system. its directed to the presidential power to make legislations will not disregard to UUD 1945.