The utility model relates to an improved special steel tube butt connector groove, which is characterized in that a groove with inclination angle of alpha is arranged on the side with strong welding material dilution rate, of a special steel tube base metal, a groove with inclination angle of beta is arranged on the side with poor welding material dilution rate, of the special steel tube base metal, a boss with length of a and thickness of b is disposed on one side of the groove with the inclination angle of alpha, and a boss with length of c and thickness of b is disposed on one side of the groove with the inclination angle of beta, wherein c is larger than or equal to zero and smaller than a. The improved special steel tube butt connector groove has the advantages that the groove is simple and convenient in processing and easy in operation, and can complete one-step formed chamfer through a machining form or by means of manufacturing a corresponding knife. In addition, the improved special steel tube butt connector groove can realize through welding without utilizing filling materials when the root of the groove is in backing welding, and chemical constituents and performances can be balanced by means of adjusting the lengths of the bosses during a welding process of special steel butt connectors.