Marcus Gunn jaw-winking syndrome (MGJWS) is a rare congenital cranial dysinnervation disorder that causes eyelid ptosis during jaw movement, usually seen in childhood. The importance of diagnosing Marcus Gunn jaw-winking syndrome in adults lies in identifying this rare congenital or, less commonly, acquired condition, which may persist or emerge later in life and is characterized by distinctive eyelid movements associated with jaw movement. Recognizing the syndrome in adults is crucial due to its functional and cosmetic implications, such as eyelid drooping (ptosis), social or aesthetic concerns, and the oculocardiac reflex, resulting in cardiac arrhythmias or even cardiac arrest, which necessitates that surgeons must conduct a prior comprehensive preoperative Electrocardiogram (ECG) assessment before considering any ophthalmic or dental surgical procedures. We report such a rare case of MGJWS in a 60-year-old man, including detailed clinical features and management modalities with congenital eyelid synkinesis.