Onycholysis is also referred to plummer's nails is a dermatological nail disorder characterized by spontaneous distal separation of the nail plate from the free margin and progressively proximally. We discuss a case of the 38-year-old man with onycholysis associated with hyperthyroidism due to Graves' disease. In this case review, we will discuss an association of onycholysis with thyroid disease and its diagnostic prognosis. Any unexplained onycholysis should prompt the clinician to investigate the client for asymptomatic hyperthyroidism.