The invention relates to medicine, in particular, traumatology and orthopedics and can be used in treatment of interphalangeal joints.Endoprosthesis of proximal interphalangeal joint has a proximal articulation head with leg and distal articulation head with leg.Novelty of the claimed endoprosthesis interphalangeal joint consists in the fact, that the proximal junction the head has the shape, close to anatomical, namely, side has profile of semicircle, radius of which is equal to R of 2.7 - 4.8 mm, and in the front - profile trapezium with angle between sides of 30 degrees and width of lower base H, equal to 7.7 - 13.4 mm, in the middle of the proximal joint head is made circular groove width h, equal to 2.7 - 4.7 mm and depth of m, equal to 0.5 - 0.9 mm, with side legs proximal articular head has the ribbed surface with lesenkami, leg has a shape of cone with angle of 4 degrees, upper base of k, which has diameter of, equal to 1.8 - 2.8 mm, and length l1 equal to 9.0 - 14.0 mm, leg has 4 longitudinal projections, 3 - 5 transverse grooves and displacement of b of relative to center of proximal joint head, which is equal to 0.4 - 0.8 mm, the proximal articular head is inclined relative to the axis at 20 degrees; distal junction the head has the shape, close to oval, and height of which is equal to 5.1 - 8.6 mm, width of the is equal to 9.3 - 12.6 mm, with side legs distal articular head has the ribbed surface with longitudinal and transverse grooves, from opposite from leg side distal articular head has cylindrical cavity, radius of which r2 is equal to 3.6 - 6.2 mm, depth of h2 is equal to 0.8 - 1.4 mm, cylindrical recess has scallop width with, equal to 1.8 - 3.8 mm and height of f, equal to 0.4 - 0.8 mm, leg distal joint head has a shape of cone with angle of 12 degrees, upper base of which k2 has diameter, equal to 1.9 - 2.4 mm and length of l2, equal to 7.0 - 13.0 mm, leg has 4 longitudinal projections, 1 - 4 transverse grooves and displacement of b2 relative to center of distal joint head, equal to 0.1 - 0.25 mm.