Motivational internalism is roughly the view that moral judgement necessarily involves some degree of motivation to act morally. Kantians and non Kantians scholars in general agree that Kant is committed to motivational internalism. However, in the recent literature some contemporary Kantians have defended a form of motivational internalism that, given Kant’s theory of motivation and rational agency, he cannot possibly hold. I argue that in order to clarify the nature of Kant’s motivational internalism, we need to consider the main features of Kant’s theory of motivation and rational agency. I show that, although it is not often recognised, Kant is in fact committed to two different internalist claims. The conclusion of the paper is that Kant’s motivational internalism is of a very different kind that the one discussed in current debates of metaethics.