Electrocardiography (Electrocardiogram — ECG) is the recording of electrical activity in the heart to examine the functioning of the heart muscle and neural transmission system. The graph obtained from this record is called electrocardiogram and the device used to record this graph is called electrocardiograph. In this study, a method based on second-order filter use was proposed to remove the white Gaussian noise on the ECG signal. The ECG signal was first subjected to a preprocessing using a low-pass filter. White Gaussian noise is added to the output signal obtained from the pre-processing result at certain levels. From level 3 Discrete stationary wavelet transform is removed from noise by using ‘SYMP’ from Symlet family, ‘DB10’ from Daubechies' family and ‘COIF1’ from Coiflet family. For each case, the ‘R’ peaks of the signal obtained after the Discrete Stationary Wavelet Transform are determined and the heart rate is found for the ECG signal.