We report a case of unusually long-lasting remission of type 1 diabetes (T1D). The patient, a Caucasian man, at the age of 43 years developed a ketotic diabetes, classified as type 1 based on clinical presentation and positivity for islet autoantibodies. Shortly after diabetes onset, oral topiramate was added to preexisting valproic acid for generalized seizures and maintained thereafter. Initial intensive insulin treatment was rapidly reduced to low doses (3 Units/day) maintained for a long time and then discontinued at month 55; fasting glucose and glycosylated hemoglobin were basically normalized at 58 months. An oral glucose tolerance test performed at month 53 showed an impaired fasting glucose (6.0 mmol/l) and a value slightly above the threshold for the diagnosis of diabetes at 2 h (11.2 mmol/l). We hypothesize that this unusually prolonged preservation of β-cell function might be ascribed to the concomitant therapy with topiramate, an antiepileptic agent with demonstrated efficacy as antidiabetic in type 2 diabetes (T2D). Topiramate should be further investigated as candidate agent for the preservation of β-cell function also in T1D.