In this study, it was surveyed to know whether an oral single dose of OLEUROPEIN could mimic the cardiac preconditioning in rats’ hearts or whether its prolonged oral administration could protect the heart against the aconitine-induced arrhythmia in rats.Eighty male Wistar rats were divided into two series (n=8 in each group). In the first series, all groups (except the control (Con) group) were given a single oral dose of OLEUROPEIN (20 mg/Kg) 1, 3, 24 and 48 h before the infusion of aconitine. In the second series, except the Con group, the other four groups were given oral OLEUROPEIN (20 mg/Kg/day) for 3, 7, 14 and 28 days, before the infusion of aconitine. Electrocardiogram was recorded to monitor arrhythmia.Data of the first series showed that the initiation time of arrhythmia, the initiation of ventricular tachycardia (VT), the numbers of reversible ventricular fibrillation (VF) and the death time had no significant difference compared with Con group. In the second series, a significant protection was occurred only in the 28 days group that was evident with increased initiation time of arrhythmia, increased initiation time of VT, and increased the number of reversible VF and death time in compared to the Con group.The findings of this study show that the oral administration of a single dose of OLEUROPEIN could not mimic the preconditioning effects in rat hearts, but the prolonged administration of OLEUROPEIN for about four weeks could protect the heart against aconitine-induced arrhythmia.