FIELD: machine building. SUBSTANCE: invention relates to traction couplings. Stabilizing traction-coupler of uniaxial trailer comprises traction lever. Lever with front part is connected with tractor via hinge fixture, and rear is rigidly connected with trailer frame. Frame rests through sprung axle and running wheels on bearing surface of roadway. Fastening of front part of lever with tractor is made in form of cross-shaped hinge equipped with spider. Cross-piece is formed from two axes interconnected rigidly. One of axles is located in horizontal plane transversely to lever and is connected by means of rotating in vertical transverse plane of flange yoke with rear part of tractor, and second is located in vertical longitudinal plane passing through longitudinal axis of trailer, and is connected to lever by means of yoke. Fork is rigidly fixed on lever end. Axis of the spider located in the vertical longitudinal plane is installed at an angle to the surface of the roadway. Upper end of said axle is shifted towards trailer frame. EFFECT: higher stability of straight-line motion and higher critical speed. 1 cl, 3 dwg