Sthenidas was a philosopher from the Roman Imperial period, likely active in the 2nd or 3rd century CE. He is associated with the Middle Platonist and Neopythagorean schools of thought, which blended Platonic philosophy with ideas from Pythagoreanism and Stoicism. No details of his personal life or origins are known.

He is credited with a single work, a treatise titled On Kingship (Περὶ Βασιλείας). This text does not survive in full but is known through fragments and summaries preserved by later philosophers, particularly the Neoplatonist Proclus in the 5th century CE.

His significance lies in his contribution to a popular genre of political philosophy. In his treatise, Sthenidas argued that the ideal ruler should be a "living law," whose authority is modeled on the divine governance of the universe. According to modern scholars, his work represents a synthesis of Platonic political theory and theological concepts typical of his era. Though a minor figure, his ideas were studied by later thinkers within the Platonic tradition, illustrating the ongoing development of political thought in antiquity.