To explore the brain processing characteristics of traditional Chinese medicine(TCM) professionals in judging the mutual generation and restriction among five elements.Methods:Relation judgment paradigm was used to group the five elements into word pairs of mutual generation and restriction，and event related potential(ERP) and functional magnetic resonance imaging(fMRI) were adopted to record and analyze the subjects' response time，correctness，evoked EEG components and the activation of brain regions in judging the mutual generation and restriction among five elements.Results:Behavioural results showed that the response time of the subjects in mutual generation was shorter than that in mutual restriction(P<0.01).ERP results indicated that both conditions induced P200，P300 and late positive component(LPC)，and the average amplitude of mutual generation was larger than that of mutual restriction(P<0.05).In fMRI experiment，the right inferior parietal lobule was activated by mutual restriction; compared with mutual generation，mutual restriction additionally activated the right superior parietal lobule and the precentral gyrus of frontal lobe; compared with mutual restriction，mutual generation additionally activated the right medial frontal gyrus，paracentral lobule，and insula and the left cuneus.Further region of interest(ROI) analysis revealed that both cuneus(BA18) and superior parietal lobule(BA7/8) had more significant activation by mutual generation.Conclusion:Brain processing of the mutual generation and restriction among five elements is similar to that of classification relationship，and mutual generation consumes more cognitive resources than mutual restriction.This suggests that judging of the mutual generation and restriction among five elements is a cognitive strategy based on the processing of classification relationship，and whether the word pairs are consistent with mutual generation is the core of classification processing.