The invention relates to a vertical type electric heating tube of a double-protection pipe, and relates to the electric heating tube; the features are that the bottom of an external layer protection steel tube is sealed, and the top is fixedly provided with a lower connecting disc; 2-6 heating inner tubes are arranged in the external layer protection steel tube; one of the heating inner tubes is afull heating inner tube with a small power, and the resting heating inner tubes are local heating inner tubes with a large power; the heating inner tubes and wiring pile heads are connected on the upper connecting disc; the middle and lower portions of the external layer protection steel tube are filled with a molten salt; the lower and upper connecting discs are provided with positioning pins and connecting disc connecting holes; the center of the upper connecting disc is provided with a molten salt inlet/outlet. The outer surface of the external layer protection steel tube can be hardly scaled; the vertical type electric heating tube of the double-protection pipe is safe and reliable in structure, long in insulation time, long in life, energy saving, easy to use, even in heating, and has popularization values.