The extraction and identification of ECG (electrocardiogram) signal characteristic parameters are the basis of ECG analysis and diagnosis. The fast and precise detection of QRS complexes is very important in ECG signal analysis; for it is a pre-requisite for the correlative parameters calculation as well as for correct diagnosis. In our work, firstly, the modulus maximum of wavelet transform is applied to the QRS complexes detection from ECG signal. Once there are mis-detections or missed detections happening, we utilize the Golden Section Search algorithm to adjust the threshold of maxima determination. The correct detection rate of the QRS complexes is up to 99.6% based on MIT-BIH ECG data.