The invention discloses an insulator mounting bracket and a mounting method, comprising the following steps: a cross arm and a first adjusting device; The cross arm is provided with a first mounting hole and a first connecting hole; The first mounting hole is used for mounting the telephone pole, and the first connecting hole is used for mounting the insulator body. A second mounting hole is arranged on the inner wall of the first mounting hole; The first adjusting device comprises an adjusting lever, a gear lever, a gear wheel and a first pressure plate; One end of the gear lever is installedin the second mounting hole, the other end of the gear lever is connected with the first pressure plate, the gear is meshed with the gear lever, the adjusting lever is connected with the gear, the rotation of the adjusting lever can drive the gear to rotate, and the rotation of the gear can drive the gear lever and the first pressure plate to move along the axis of the gear lever. The insulator mounting bracket and the mounting method of the invention are used for mounting the insulator and have the advantages of stable mounting and adaptability to bad weather environment such as strong windand the like.