The ketogenic diet (KD) has been used for a long time as a therapeutic approach for drug-resistant epilepsy. It is a high-fat, low-carbohydrate, and adequate protein diet. There are various types of KD with some differences in their compositions that mainly include classic KD, medium-chain triglyceride diet, modified Atkins diet, and low glycemic index treatment. The anti-seizure mechanisms of KDs have not yet completely understood but, some possible mechanisms can be theorized. The aim of the present study was to review the various types of KD and explain the probable biochemical mechanisms involved in its anti-seizure property.