Death due to plant poisoning is more come in southern India. Of which oleander seed poisoning is the number cause of plant poisoning. Though the chemical nature and symptomatology of this poison has been well described, there is no defined protocol for managing such a great social issue and it warrants larger studies. This study was done to assess the clinical manifestations in yellow oleander seed poisoning and to study the electrocardiographic changes and biochemical abnormality associated with it and to correlate the number of seeds and its form of consumption with the severity of ECG changes. We have also revealed slightly higher incidence of poisoning in females like in most other previous studies. Severe cardiac manifestations were related to delay in admission, grounded or paste from of consumption, and in those who developed electrolyte imbalance like hyperkalemia. Study revealed ECG abnormalities in about 27% of patients. We have also shown from our study that those who had consumed more than 8 seeds had 100% severe cardiac manifestations. The ECG abnormalities in males exceeded the females by nearly 18%. ECG abnormalities appeared as early as 5 hrs and as late as 10 Hours of poisoning. Sinus bradycardia was the commonest arrhythmia observed in our study.