Abstract: This article analyzes Nietzsche’s critique of the metaphysical concept of freedom throughout his works, from Human, All Too Human (1878) to On the Genealogy of Morality (1887) and Twilight of the Idols (1888). It argues that, in criticizing the metaphysical concept of freedom, Nietzsche aims to target the metaphysical concept of substance that lies at its core. Substance is Nietzsche’s real target: while declaring men free, metaphysics actually makes them unfree by conceiving of them as substantial beings. Men are regarded as an unchanging essence, a substance with fixed intentions, from which actions emerge independently from each other in a kind of creatio ex nihilo. In light of its substantial conception of men’s being, metaphysics deprives men of the freedom to develop their character, personality and ultimately of the freedom to become masters of their own destiny.