Method and device for identifying object

Provided are an artificial intelligence (AI) system for simulating functions such as recognition, determination, and so forth of the human brain by using a mechanical learning algorithm like deep learning, or the like, and an application thereof. The disclosure relates to a method, performed by a device, of identifying an object, and the method includes obtaining an image including an object, extracting attribute information of the object from the image by using a plurality of layers included in a network for determining a category of the object, obtaining feature information representing the object by combining attribute information extracted from at least some layers among the plurality of layers by using at least one feature extraction layer, and identifying the object based on a result of comparing the obtained feature information with feature information of each of a plurality of previously stored object images, wherein a parameter of each of the at least one feature extraction layer is configured according to a training result based on a database including a plurality of images.