The invention relates to a fuzzy Petri inference method of an intelligent alarm expert system of a transformer substation. After an alarm signal is obtained by the intelligent alarm expert system of the transformer substation, a rule knowledge base represented by a fuzzy production is searched by an inference engine, all rules associated with the alarm signal are searched, fuzzy Petri sub-networks corresponding to all fuzzy productions are established, an integrated fuzzy inference Petri network is formed, and Token values are added in all alarm signal libraries; the fuzzy inference Petri network judges whether to trigger according to the conditions; if triggering, the fault reliability is figured out to determine whether the corresponding fault treatment is preformed. The method provided by the invention can be used for deducing the possible inference result from the single event, handling the inference of the associated event well to ensure the comprehensiveness and accuracy of the inference of the associated event, and evaluating the priority level according to the reliability of the inference result and the processing scheme to remove the unrelated information, thus the processing efficiency is increased and the erroneous judgment is reduced.