The invention relates to a universal grounding wire, which comprises a grounding head. One end of the grounding head is provided with a connection plug; the connection plug and a first connection seat form detachable connection; the first connection seat and a second connection seat form rotary connection; a rotation limiting mechanism is arranged between the first connection seat and the second connection seat; the second connection seat and the first connection seat are electrically conducted; the second connection seat is connected with an insulated rod; and a grounding wire is arranged on the second connection seat. According to the above grounding head for connecting a device, through the rotary connection between the first connection seat and the second connection seat, the rotation limiting mechanism is used to execute limiting of the rotation angle between the first connection seat and the second connection seat, adjustment of an angle between the grounding head and the insulated rod is thus realized, grounding requirements at different positions can be met, and the operation is convenient.