Experiment study of a method for locating ECG key points is introduced in this paper.Key points of QRS complexes and T waves are located accurately by using local transform algorithm. Based on locations of positive and negative peaks ,a method of classifying QRS complexes and using difference of peak values idendifying polarities of T waves,is presented. The local transform algorithm stresses features of key points and good uniformity is found. The calculation of the methods of discrimination of locations o...