The invention relates to the technical field of power communication network equipment fault diagnosis, in particular to a power communication network equipment fault diagnosis method based on multi-controller cooperation, which is applied to an SDN (Software Defined Network) and comprises the following steps: a fault propagation model based on a Bayesian decision theory is constructed; the plurality of sub-controllers receive the network symptom information sent by the transponder and then send the network symptom information to the main controller; the main controller generates FPM abstract request information and sends the FPM abstract request information to the related sub-controllers; the sub-controllers generate FPM abstracts and then send the FPM abstracts to the main controller forcombination; the main controller generates FPM information for fault diagnosis. The method can improve the fault diagnosis efficiency, and can be suitable for a network environment formed by a plurality of controllers.