Mars lies on his back, deeply asleep, his body naked and undefended. His weapons and armour have been taken from him and now sit in the hands of small fauns playing in the middle ground of the scene, one of them blowing a conch shell close to Mars's ear without waking him^[2]. Venus, by contrast, is richly dressed in the manner of a young woman from a distinguished Florentine family, and she remains alert, watching over the sleeping god rather than sharing his abandon^[2]. The contrast is the entire subject: a god of war rendered harmless, and a goddess whose composure marks her, rather than him, as the figure in command of the scene.

On the right side of the panel, wasps emerge from a hollow tree trunk close to Mars's head. Wasps in Italian are vespe, and the detail has long been read as a visual pun pointing to the Vespucci family, one of the more prominent families in Botticelli's Florence, as the likely patrons of the picture^[1]. Its long, narrow format, small-scale figures and low horizontal composition all suggest the panel was made to be set into a piece of furniture, most plausibly a wedding chest or a backrest, rather than framed and hung independently^[1]. Botticelli was not alone in painting this subject for the Vespuccis: similar Mars and Venus compositions were produced for the same family by other Florentine painters of the period, including Piero di Cosimo and Jacopo del Sellaio^[1].

Several literary sources have been proposed as inspiration for the composition. The Roman poet Lucretius opens his De Rerum Natura with an invocation to Venus in which Mars, conquered by love, casts himself into her lap; the image of the god lying back with his neck exposed while gazing up at the goddess closely matches the pose Botticelli gives him^[3]. Closer to home, the Florentine poet Poliziano's Stanzas for the Joust describes Cupid finding Venus seated on the edge of a bed, freshly disentangled from the arms of Mars, who lies on his back in her lap gazing at her face, a scene near enough to Botticelli's arrangement that some scholars have taken it as a direct source^[3]. Lorenzo de' Medici's own Hymn to Mars and Venus, along with the ancient poets Lucian and the late antique writer Reposianus, have also been named among the literary currents feeding into the picture^[1].