A device for the cerclage of an anal canal (CA), said anal canal (CA) having an extension along an axis (Y-Y) and an initial cross section (B) and being encircled around its periphery by a first internal muscular wall (SI) and a second external muscular wall (SE) encircling the previous one, comprising: - a central tract defined by at least two opposing walls and having within it a cavity having a width (D) transversally, at least in one portion; said width (D) being defined, within the cavity , by the distance between the two opposing walls , the central tract terminating at either end with a first terminal end and a second terminal end opposite each other; - a first tract , integrally connected to the central tract at said first terminal end by means of a connecting portion and extending the central tract , the first tract ending with an engagement element having a transversal width, at least for a tract, of size (S); said size (S) preferably being larger than the width (D) of the cavity ; said device having a rest configuration, in which the central tract extends along a longitudinal axis (X-X) and the second terminal end of the central tract and the first tract are uncoupled from each other, and an active configuration, in which the central tract and first tract are coupled with each other, giving the device a closed ring shape subtending an area (C) within it defining a smaller final cross-sectional area (B') on the anal canal (CA) than the initial cross-sectional area (B); wherein said central tract and said first tract create, in the active configuration of the device, an interpenetration coupling defined by the insertion of the engagement element within the cavity , wherein the device further comprises locking means active between the first tract and the central tract to prevent sliding between them, wherein said engagement element is defined bv a spherical body with a diametrical section equal to (S), and wherein said locking means are active on the central tract to define a squeezing of the cavity upstream of the engagement element ; said squeezing preventing the spherical body from coming out from the cavity , and in that said first tract is defined by a cylindrical tract , having a direction of extension along a longitudinal axis (X-X), ending with the engagement element , and in that the cavity extends along the whole length of the central tract along a longitudinal axis (X-X) thereof so that the translation of the spherical body inside the cavity can be varied as desired and, bv adjusting the depth of penetration of the spherical body inside the cavity , it is possible to dimension the closed ring-shaped contour (K-K) of the device as desired, according to how much one wishes to compress the initial cross section (B) of the anal canal (CA). - a central tract defined by at least two opposing walls and having within it a cavity having a width (D) transversally, at least in one portion; said width (D) being defined, within the cavity , by the distance between the two opposing walls , the central tract terminating at either end with a first terminal end and a second terminal end opposite each other; - a first tract , integrally connected to the central tract at said first terminal end by means of a connecting portion and extending the central tract , the first tract ending with an engagement element having a transversal width, at least for a tract, of size (S); said size (S) preferably being larger than the width (D) of the cavity ; <EOS>