A tool for crimping a cable connector (6) comprises a first, U-shaped arm (3) which defines a seat in which the connector (6) may be accommodated in the working position; a second, compression arm (1) suitable for exerting a compression force on the connector (6), comprising a compression profile (5) at one end thereof, which, in turn, comprises a number of rotation pins which project laterally outwards from the compression profile (5) and are suitable for penetrating into corresponding holes in a branch of the first arm (3), to keep the second, compression arm (1) joined to the first arm (3).