Disclosed are an artificial neural network device and a method of operating the same. The artificial neural network device includes an operation part performing an artificial neural network operation on an input feature map and a classification part performing a classifying operation on the input feature map based on the artificial neural network operation of the operation part. The operation part includes an XNOR operation circuit performing an XNOR operation on the input feature map and a filter and a binarizing circuit performing a binarization operation based on the result of the XNOR operation of the XNOR operation circuit. Accordingly, the artificial neural network device is miniaturized and performs the operation at high speed.