The invention relates to the technical field of electric power, in particular to a coaxial cable joint disassembling device which is convenient to use, easy to operate and fast to master and improves the construction efficiency. The coaxial cable joint disassembling device comprises a power mechanism and a locating mechanism. The power mechanism comprises an electric drill, a transmission shaft and a friction wheel. The friction force wheel is arranged at the front end of the transmission shaft to rotate along with the transmission shaft. The locating mechanism comprises a clamping body and a locating support. The clamping body coats the periphery side of the transmission shaft. The friction wheel extends out of the front end of the clamping body. An outer ring of a bearing is sleeved with the clamping body through a fixing end in a connected manner. A locating support is further arranged at the front end of the clamping body. The locating support extends axially and coats the periphery side of the friction wheel. According to the coaxial cable joint disassembling device, by means of the locating mechanism, the tool operation position can be determined precisely, and the friction wheel can be closely attached to a coaxial cable joint. A bidirectional rotating part drives bidirectional rotating friction of the friction wheel, the functions of fixing and disassembling the coaxial cable joint are achieved, the working efficiency is improved effectively, and operation safety is promoted.