The present article re-examines the iconography of a medal of Bartolomeo Colleoni (1395–1475), one of the most renowned condottieri of the Italian Quattrocento, produced by a Venetian medallist, Marco Guidizani. On the obverse Colleoni is represented as a captain-general of the Republic, identified also by a cognomen ‘Caput Leonis’ (head of a lion). The reverse shows an all’antica looking nude male figure holding a plummet (symbol of Justice and Equity) seated on a cuirass – a male counterpart for the Venetian Lady Justice. The medal is recognised as probably modelled on the coinage of Alexander the Great presenting the leonine physiognomy of the Macedonian king on the obverse and a figure of Zeus enthroned on the reverse, the specimens of which were held also in Venetian collections. Especially the massive silver tetradrachms were quite popular as collectibles during the Renaissance, as they bore Alexander’s portrait ‘confirmed’ by an inscription (Alexandrou – of Alexander). The Macedonian king was seen as both a great warrior and a great philosopher, whose undertakings were intended to build a better state. The iconography of Guidizani’s medal was very unusual when compared to earlier condottieri medals, usually presenting their subjects in military triumph, and invoking the virtues of courage and strength. Here the soldier rejects his military identity, turning himself into a just judge and benefactor. This composition was conceived in particular political circumstances, in which, it seems, no demonstration of military force was needed, giving way to other virtues such as justice, prosperity and peace. The medal may be perceived as part of a wider political programme of the city’s governing bodies. Therefore the message conveyed by Colleoni’s medal does not present the condottiere’s own self-fashioning concept, but transmits his patron’s idea of a ‘perfect captain’ in the time of peace.