Ketogenic diet (KD) is one of the effective treatments for refractory epilepsy (RE) and is recommended when anti-seizure medications (ASMs) are ineffective or less effective, inoperable or ineffective. The efficacy of the medium-chain triglyceride (MCT) ketogenic diet is as good as the classical KD (CKD), which has been demonstrated in several retrospective, prospective, and randomized studies, and MCT is more ketogenic than long-chain triglycerides, so MCTD allows more carbohydrate and protein foods, which makes MCTD more palatable than CKD more palatable. Research advances in the mechanisms and clinical efficacy associated with MCTD in the treatment of refractory epilepsy are reviewed.