In most of the Greco-Roman historical writings about Alexander an important place is given to the question of Alexander’s friends, either to enhance his generosity, confidence, fidelity towards them, or to denounce his cruelty against his closest companions. Several reasons contribute to the interest of ancient writers to such a question : an institutional one (role of the hetairoi in the Macedonian monarchy) ; a mythical one (influence of the epic motif of heroic friendship, and of the exemplary pair formed by Achilles and Patroclus) ; a social reason (high rank occupied by friendship in the moral values of Antiquity, and particularly in ancient political thought, with special emphasis put upon the distinction between friends and flatterers, and upon the aptitude for friendship as a dividing line between king and tyrant). The aim of the present paper is to explore the use of this friendship motif in the Alexander Romance, a largely fictional biography of the Macedonian conqueror, of a rather encomiastic kind. The dealing of the motif is studied in the successive rewritings of the Romance, especially in the original alpha recension (3rd c. AD ?) and in the christianized epsilon recension (8th-9th c.). In the alpha recension, the investigation focuses upon the choices made by the redactor among the material inherited from the historical tradition (censorship of inconvenient elements, amplification of positive ones). In the very innovative epsilon recension, the treatment of the friendship motif has been profoundly transformed, and much amplified. The many friends who surrounded Alexander in the former recensions and were sometimes very elusive figures have been replaced by a reduced team of four close friends, avatars of the four successors of Alexander alluded to in the Book of Daniel. The influence of the Bible may also explain the invention of Charmides, a new fictional character, whose friendship with Alexander is reminiscent of that of Jonathan with David. Such a similitude between the protagonist of the Romance and the Biblical king, mythical model of all the Byzantine emperors, was well fit to favour the transformation of Alexander’s story into a mirror of princes.