This paper presents a method to automatically detect arrhythmia based on the prominent peak detection and Poincare plot. The R-R interval of arrhythmia or irregular ECG, which are different from those of normal ECG. The Poincare plot of R-R interval signal is illustrated here and characteristic indexes are extracted from the plot. The prominent peak detection is obtained for normal and arrhythmia and we have calculated the beats per minute count to characterize the comparison between normal ECG and arrhythmia. © Research India Publications.