The invention provides a folding arm disconnecting switch maintenance method, which is implemented by using a special tooling platform designed in a matching manner. The folding arm disconnecting switch maintenance method comprises the following steps such as: (1) placing the special tooling platform to a set station and performing horizontal calibration; (2) fixing the disconnecting switch on thespecial tooling platform; (3) dismounting an upper conductive arm; (4) dismounting an intermediate joint; (5) dismounting a lower conductive arm; (6) disassembling the upper conductive arm; (7) dismounting a clamping spring; (8) disassembling a moving contact assembly; (9) reassembling after maintenance and treatment; and (10) debugging. The folding arm disconnecting switch maintenance method provided by the invention is implemented by using the special tooling platform designed in a matching manner; compared with the common methods in the prior art, the folding arm disconnecting switch maintenance method can greatly reduce the number of personnel required for on-site maintenance, save manpower, greatly improve maintenance efficiency, and shorten maintenance time; therefore, the time of maintenance and power failure is greatly reduced, which has good economic and social benefits; and the folding arm disconnecting switch maintenance method can effectively protect the relevant components of the disconnecting switch, therefore, the quality of maintenance is improved.