Analysis and reconstruction of ECG wave from sampled data is an important aspect in estimating the physiological condition of heart as well as in transmitting the ECG data to a remote location. In the present paper software based off line Fourier analysis technique has been reported to find the harmonic components of ECG wave of a normal subject. The respective Fourier harmonic data have been combined to reconstruct the ECG wave and thus to find the maximum number of harmonic present in a normal ECG wave. The analysis results are reported in the paper and it has been observed that complete reconstruction of ECG wave is possible if only fifteen Fourier harmonic data are considered. Thus transmission of ECG wave may be easier since fifteen harmonics amplitude are only required to be transmitted along with their respective phase angles. © 2008 IEEE.