Abstract: AIM:To investigate diagnosis and analysis of localization characteristics of transesophaged atrial pacing in concealed accessory atrioventricular pathway. METHODS: We retrospectively analyzed 360 cases of concealed accessory atrioventricular pathway, which were diagnosed by intracardiac electrophysiology and concluded their characteristic manifestation transesophaged atrical pacing. RESULTS: The sensitivity of inverted P wave in lead I in the diagnosis of left-sided accessory pathways was 69%, and the specificity was 98%, The sensitivity of upright P-wave in lead V1 in the diagnosis of left-sided accessory pathways was 71%, and the specificity was 88%. The sensitivity of bidirectional P’ wave in V1 lead in the diagnosis of left-sided accessory pathways was 14%. Specificity was 95%, sensitivity of RPERPV1 in the diagnosis of right-sided accessory pathway was 82%, and the specificity was 100%. CONCLUSION: Analyses of the P wave characteristics in leadⅠand V1 and measuring or contrasting RPE and RPV1 has a significant value of diagnosis and localization of concealed accessory atrioventricular pathway.