Does Aristotle attribute to the nutritive soul a function specifically dedicated to the embryonic formation? The claim has sometimes been defended in the Aristotelian tradition or by modern scholars. This article intends to show that Aristotle never uses such formative power. The whole embryogenesis is the work of the nutritive soul inasmuch as it makes the living thing grow. Through a close reading of texts from de Anima II,4, de Generatione Animalium II,1, 4 and 6, we establish that (i) Aristotle distinguishes two stages in the generative process of the embryo: the generation (understood in a restrictive meaning) of the heart by an external principle (the male’s seed) and the growth of the heart and of the whole embryo by the action of the internal principle located in the heart; (ii) Aristotle sometimes makes a more accurate distinction between the initial “constitution” of the organs and their growth. Even in this case, these two processes depend on the soul’s “productive power”, which is the same as the one by which the nutritive soul makes the living thing grow. There is no conflict on this point between the de An. and the GA. The growth of the adult animal and the whole formation of the embryo depend on a single function of the nutritive soul, the “use of the food”. This result confirms the unity of the functions of the nutritive soul in Aristotle’s psychology and embryology.