Menecrates of Syracuse was a Greek physician who lived and worked in the 4th century BCE. He served as a doctor to the Macedonian king Philip II, father of Alexander the Great. While his medical writings have been lost, he is remembered in history almost entirely for his exceptionally arrogant and eccentric behavior as described in later anecdotes.

According to these stories, Menecrates believed his healing skill granted him a divine status. He reportedly demanded that his patients call him "Zeus" and treated them as his subjects. One famous tale describes him hosting a dinner where he alone ate food meant for the gods, while his patients were given ordinary meals, leading to a confrontation with King Philip. Modern scholars recognize these accounts are likely exaggerated, but they suggest Menecrates was a prominent and controversial figure in his time.

His historical significance lies not in any surviving medical theory, but in what his story represents. He is often cited as an extreme example of the tensions between a physician's professional authority and social norms. Menecrates serves as a memorable case study in discussions of ancient medical ethics, the doctor-patient relationship, and professional hubris.