The invention provides a coating method for growing a barrier layer composite film of a second-generation high-temperature superconducting strip, comprising the following steps: S1, installing the base tape on a drive system, and adjusting the vacuum degree of the coating environment; S2, turning on the drive system, Carry out forward tape running; open the cathode system, prepare the first barrier layer after target washing and coating, and close the cathode system and drive system after completion; S3, open the drive system, and carry out reverse tape running; open the cathode system, wash After target and coating, the second barrier layer is made, and the cathode system and drive system are closed after completion. The invention effectively reduces the friction of the system, increases the coating area of the strip, improves the production efficiency, and reduces the manufacturing cost of the strip; at the same time, the preparation of the composite film layer through the reciprocating motion reduces the evacuation time; one cavity realizes the preparation of two materials , greatly reducing the equipment footprint. Therefore, it is more suitable for large-scale industrial production of the second-generation high-temperature superconducting tape barrier layer composite film.