Provided is a covering membrane provided within a duodenum. This invention relates to a medical device placed in the digestive tract. At least a part of the duodenal internal covering membrane is prepared from a hydrophobic and oleophobic material and is biodegradable. The duodenal internal covering membrane further includes a biomimetic microarray adhesive sheet, an elastic piece, an anchor hook, and an anti-twist rib. The duodenal internal covering membrane is prepared by electrospinning and can be used to prevent and treat obesity and diabetes.