The invention discloses a screw tap, in particular a hot melting drilling tapping thread forming tap. The hot melting drilling tapping thread forming tap comprises a handle part, a tapping drill bit and a hot melting drill bit, wherein the handle part, the tapping drill bit and the hot melting drill bit are integrally molded; the hot melting drill bit is positioned at the front end; the tapping drill bit is positioned in the middle; the handle part is positioned at the tail end; the diameter of the tapping drill bit is larger than the diameter of the hot melting drill bit; the diameter of the handle part is smaller than the diameter of the hot melting drill bit; and the tapping drill bit is a thread forming tap. The hot melting drilling tapping thread forming tap combines two procedures of hot melting drilling and internal thread processing as a whole, and has the advantages of simplicity, convenience, high positioning precision, good thread quality and high working efficiency compared with traditional processing by two tools (the hot melting drill bit and the thread forming tap); as the thread forming tap is used for chipless processing, molded surfaces of threads are full, and the thread connecting strength is improved; the hot melting drilling tapping thread forming tap is an internal thread processing tool with excellent performance, and in particular, is suitable for drilling and tapping various black metals, stainless steels and such nonferrous metals as copper and aluminum alloys.