The invention relates to a radio frequency coaxial cable signal calibrator. According to the structure of the radio frequency coaxial cable signal calibrator, coaxial connectors of different types are arranged at the two ends of a shell respectively and metal cores and metal covers of the two coaxial connectors are in short connection respectively; a light emitting diode is arranged on the shell, one diode corner of the light emitting diode is connected with the metal cores of the coaxial connectors, and the other diode corner of the light emitting diode is connected with the shell. The radio frequency coaxial cable signal calibrator can rapidly distinguish a signal sending line from a signal receiving line in a pair of 2M lines. In 2M signal butt joint operation, accurate butt joint is achieved at a time.