The present application provides an identity authentication method and an apparatus. The method may include obtaining a sequence of depth images containing a target face and a sequence of original two-dimensional (2D) images containing the target face, and performing identity authentication. The identity authentication may be conducted by: calculating a target face three-dimensional (3D) texture image according to the depth images containing the target face and the original 2D images containing the target face; projecting the target face 3D texture image to a 2D plane to obtain a target face 2D image; extracting feature information from the target face 2D image; comparing the feature information of the target face 2D image with feature information of a reference face 2D image to determine a similarity value; and in response to that the similarity value exceeds a first threshold, determining that the identity authentication succeeds.