Abstract: The invention relates to pipeline transport and can be used for connecting polymer pipes to each other or to metal pipes, as well as to polymer and metal containers. The polymer pipe joint assembly comprises a fitting, positioned inside the polymer pipe, a coupling, having at least one cylindrical section, which covers the pipe and fitting, wherein the assembly has a sleeve, capable of changing its geometrical dimensions and shape under pressure, said sleeve has at least one cylindrical section placed between the pipe and coupling, the fitting has a shoulder on its outside surface, restricting the movement of the pipe and sleeve, while the inside surface of the coupling has a lead-in chamfer. The change of the dimensions of the sleeve can be performed both by selecting different types of sleeve material or by its construction design.