Gastric floating glipizide controlled release tablet and preparation process thereof

The invention discloses a gastric floating glipizide controlled release tablet and a preparation process thereof. The controlled release tablet is sequentially composed of a blank tablet core, an isolating coating, an ointment applying layer and a controlled release coating from inside to outside, wherein the blank tablet core contains a bleaching assistant and other pharmaceutical adjuvants; and the mean density of the overall controlled release tablet is less than 1g/ml. The gastric floating glipizide controlled release tablet has a relatively good gastric floating effect; and the gastric emptying time is retarded, thus the detention time of the preparation in a gastrointestinal tract is prolonged; the absorption time is increased; the absorptive amount is increased; and the bioavailability is improved.