Second part of a study dedicated to possibility and existence in the philosophy of Leibniz, this article attempts to reconstruct his conception of existence, a fundamental notion that supports the entirety of his ontology, which is nevertheless neither clearly defined, nor systematized. In three parts, we establish that Leibniz’s conception of existence is a degree of possibility, an addition, a complement, which does not, however, add anything new. Existence is not a perfection, but a comparative relation of perfections between themselves. It is not a real predicate, but a logical predicate, characterized as that which is distinctively felt, as that which pleases a mind without displeasing the most powerful mind, and as that which is the most harmonious. Leibniz’s conception of existence has several layers and already prefigures to many the position of Kant.