This dissertation explores the intersections of technical medical knowledge and lay knowledge of medicine in fictional prose writings in the genre of the ancient Greco-Roman romance novel. I analyzed a sample of seven novels consisting of four Greek novels (Xenophon of Ephesus' Ephesian Tale, Achilles Tatius' Leucippe and Clitophon, Longus' Daphnis and Chloe, Heliodorus' Aithiopica) and three Latin novels (Petronius' Satyricon, Apuleius' Metamorphoses, and the anonymous Apollonius King of Tyre). These novels were written between the first and sixth centuries CE which provides a survey of literature for a lay audience under the Roman Empire. This dissertation provides a critical reading of the novels to help shed light on how medicine was perceived and represented by laypersons and to reveal what aspects of medical knowledge became widespread cultural knowledge. Heliodorus, Apuleius, and Achilles Tatius display more advanced knowledge of medicine than other novelists. In their novels we can identify social practices of the medical field, such as multiple consultation, and the many varieties of medical options available to patients, such as religious, magical, folk, and philosophical healing. They also provide examples of laypersons' perceptions and treatments of diseases other than lovesickness, such as madness and rabies. Xenophon of Ephesus, Apollonius King of Tyre, Longus, and Petronius reference medicine primarily as a social construct. The forms of medicine represented in these novels are typically folk remedies and lay attitudes towards doctors and the medical profession, and lovesickness is the main connection to medicine. The healers of these novels are generic and likely reflect laypersons' perception of real doctors. My work shows that novelists who putatively lived near large cities that attracted intellectuals such as Athens, Rome, Alexandria, and Ephesus, included more advanced and current medical knowledge than their more rural counterparts. Across all novels the idealized concept of lovesickness as a medical illness was canonized, and other healing practices involving rabies, certain types of madness, and basic first aid were integrated into society as cultural knowledge.