The invention discloses an image feature enhancing method based on a database neighborhood relation. The method includes the steps that based on an improved CNN feature extraction mode with input image size limitation removed, the optimal scales of input images are adaptively selected through a maximum energy pooling method, and therefore CNN feature extraction of database images is completed; aiming at the situation that each CNN feature in the database images moves towards the CNN features of the related images to a certain degree, the related images in a database are gathered within a certain range in feature space, and therefore the CNN features of the database images are enhanced. According to the scheme, calculation of relevance among the images can be accurately and efficiently achieved, and then the method can be applied to an image retrieval system.