ECG machine, currently on the market are generally not a function of the T-wave alternans detection analysis. Studies have shown that T-wave alternans can accurately predict sudden cardiac death, higher predictive accuracy in the case of combination of left ventricular ejection fraction (Left Ventricular Ejection Fraction, LVEF). This paper presents the design of function modules of T-wave alternans software based on the QT environment. Focus on the data processing module of the software, such as the QRS wave detection, T wave detection, the matrix of the T-wave extraction, T-wave alternans detection.