The invention relates to a pipe joint used for the connecting of a skin-effect electric heating element and a heating pipe; the pipe joint made of iron-based memory alloy material is provided with 'bound and restore' feature, and can generate a certain connected tightening force, and can be used for replacing the pipe joint made of general material; meanwhile, the problems that the pipe joint for connecting two heating pipes in heating pipe connection of long-distance pipeline electric heating pipe construction is submerged in underground water or accidental water seepage can lead the sealing of the welding seam to be unreliable, which can affect the skin-effect heating current channel, the number of the pipe joints at the heating pipe is large, the welding construction which clings to the long-distance pipeline is difficult, the difficulty of underground construction is large, the workers are more, the construction period is long, and the welding technology is low-efficient are solved; meanwhile, the invention has advantages that: the air tightness is reliable, the welding device and the corresponding personnel are not required, and the operating tool is simple.