Complexity　measurement,　approximate　entropy　can　reflect　the　characteristics　of　the　system　quickly　and　effectively.　This　paper　introduces　AE　method　which　is　seldom　used　in　ECG　detection　and　researched　the　detection　of　ventricular　disease　using　the　MIT-BIH　database.　On　ventricular　fibrillation,　ventricular　tachycardia　and　other　diseases,　the　AE　method　is　feasible,　research　shows　that　AE　is　a　sensitive　parameters　which　can　be　used　in　clinical　diagnosis.