To explore the differences in medical proposition processing among medical students with different years of study in traditional Chinese medicine(TCM) using event related potential(ERP) technique.Methods:With TCM postgraduates and sophomores as research subjects，suffix paradigm and sentence correctness judgment task were performed to extract and analyze the behavioral and EEG data of the subjects in understanding and judging TCM and western medicine propositions.Repeated measures ANOVA was used to analyze the early left anterior negativity(ELAN)，P200，N400 and late positive component(LPC) time windows.Results:In N400 time window，the sophomore group induced more negative amplitudes than the postgraduate group，and the main effect of group was marginally significant ［F(1,27)=4.01，P=0.06，η2=0.13］.In LPC time window，the interaction between groups and proposition types was distinct ［F(2,54)=3.57，P=0.04，η2=0.12］，and in the sophomore group，TCM propositions elicited a larger LPC amplitude than western medicine propositions(P=0.01).In the postgraduate group，no significant difference was found between TCM and western medicine prepositions(P=0.27).Conclusion:Students with different years of study in TCM have different understanding processes of TCM and Western medicine propositions.With the increase of knowledge level，TCM students may no longer pay attention to the metaphorical characteristics of TCM itself，and tend to concretely process the abstract TCM concepts into western medicine propositions，showing more similarities in understanding TCM and western medicine concepts.