Objective：The aim of the study was to evaluate the risk of arrhythmia induced by periplocin，the main active component of Cortex Periplocae，a traditional Chinese medicine preparation. Methods：In this experiment，isolated tissues（guinea pig papillary muscle and rabbit Purkinje fiber）were treated by 0.3，1.0，or 3.0 μmol/L periplocin to assess the effect on action potential. The following parameters and endpoints were assessed：resting membrane potential（RMP），action potential amplitude（APA），maximal depolarization rate of phase 0（dv/dtmax），action potential duration at 30%，50%，and 90% repolarization（APD30，APD50，and APD90）. Results：As compared to the 0 μmol/L group，periplocin-related significant reduction in APD30，APD50 was observed at guinea pig papillary muscle in the 0.3 or 1.0 μmol/L periplocin. Periplocin-related significant decrease in dv/dtmax was observed at rabbit Purkinje fiber in the 0.3，1.0，or 3.0 μmol/L periplocin. Periplocin-related significant reduction in APA was observed at rabbit Purkinje fiber in the 3.0 μmol/L periplocin. Periplocin-related significant reduction in APD30 was observed at rabbit Purkinje fiber in the 1.0，or 3.0 μmol/L periplocin. Conclusion：Periplocin has the potential to induce arrhythmia.