An apparatus for classifying data using a neural network includes an input layer configured to receive input data; an output value to output a plurality of first output values of the input data with respect to each of at least one of all classes, and output only one first output value of the input data with respect to each of a rest of all of the classes; and a boost pooling layer to receive one or more output values output for each class, and output one second output value for each class.