Separation of powers is one of strongest aspects of contemporary constitutionalism, mostly to rationalize the exercise of state power. In Brazil, the 1988 Constitution provides as entrenchment clause to tripartition of powers. However, there is a change in paradigms, especially at the level of constitutional jurisdiction, through the phenomena of judicialization and judicial activism because the intervention of the Judiciary in the primary functions of other powers. Using deductive and descriptive method, bibliographical and documentary research, we tried to point out the harms that the invasive action of the Judiciary causes to the functional balance between the powers and democracy.