The heart is a vital organ that pumps blood throughout the body. A healthy heart beats neither too fast nor too slow, normally 60-100 times per minute. A heart that beats too fast up to 120-300 times a minute is called tachycardia. Ventricular tachycardia (VT) is a tachycardia that occurs in the ventricles if it lasts for a long time, can lead to congestive heart failure and death. Deaths caused by heart and blood vessels are in the highest rank in the category of non-communicable diseases, based on The Institute for Health Metrics and Evaluation (IHME). To prevent an increase in deaths from heart disease, the public is expected to be vigilant by checking their heart health from an early age. Cardiac examinations can only be done at health care service, therefore the aim of this study is to build a system that can detect VT that can be done alone anywhere. To build the system, the AD8232 module is used as a signal conditioner and Arduino Uno as a microcontroller. VT heart defects can be seen from the shape of the QRS signal and the rate of the heartbeat. The parameters to be used are the RR interval and the area under QRS. The classification method uses k-NN because this method is suitable if only a few parameters and data are used. From the research results obtained 90,47% accuracy for k = 3 and k = 5, 95,23% for k = 7.