A duodenum internal covering membrane is disclosed. The covering membrane ismade of abiocompatible material and mainly comprises an elastic ampulla and a tubularpart, wherein theampulla is positioned in the duodenal bulb, the tubular part can extend to thejejunum, theampulla contains a wavy or V-shaped or trapezoidal or city wall-shaped elasticring which iscontinuously encircled, the elastic ring is made of a memory or non-memorybiocompatiblematerial, peaks, valleys and bent angles of the elastic ring are single-circlecoil springs withoutward anchor hooks, the single-circle coil springs on the lower edge arepenetrated and woundwith recovery threads, the upper edge of the ampulla is a wavy or V-shaped ortrapezoidal or citywall-shaped elastic membrane, the elastic ring and the ampulla comply with themotion of theduodenum and the bulb as a whole, and the ampulla and the tubular part can beclosed up orfolded into the shape of a ball or cylinder or capsule or spindle. The single-circle coil springshave strong elasticity, weak sharp injuries and good fixation for the recoverythreads attachedthereon, thereby being conductive to anatomical structure and basicphysiological functions ofthe duodenum. The covering membrane within the duodenum of the presentinvention can beprepared into a medical device for preventing and treating obesity anddiabetes.
