The invention belongs to the field of electric power facilities, and relates to a thermochromic bow line connecting tube. The connecting tube includes an alloy tube body and a cold shrink tube sleeve outside the tube body. The inner wall of the tube body is coated with a conductive paste layer. Anti-skid teeth are arranged on the inner wall surface of the tube body. Threaded holes are arranged at intervals in the tube walls of the two ends of the tube body along the axial direction. Alloy gaskets are arranged on the inner wall of the tube body in positions corresponding to the threaded holes. Anti-skid teeth are arranged on the surfaces of the alloy gaskets. Fastening screws are matched with the threaded holes, and are connected with the outer walls of the alloy gaskets. The outer wall of the tube body is close to the cold shrink tube sleeve. The outer surface of the cold shrink tube sheath is coated with a thermochromic ink layer. A layer of waterproof self-adhesive tape is arranged in the interlayer between the outer wall of the tube body and the cold shrink tube sleeve. The alloy tube body and the conductive paste layer on the inner wall of the tube body enhance the corrosion resistance, oxidation resistance and electrical conductivity. The matching between the fastening screws and the threaded holes makes the alloy gaskets and bow lines connected more firmly. As the ink layer on the outer surface of the cold shrink tube sleeve is thermochromic, abnormal temperature at the joint of bow lines can be clearly found, and hidden danger can be eliminated in time.