1. An image object category recognition method, comprising the following steps: an image feature extracting step (S 1 ) of extracting feature points of all sampling images in N known categories with a feature point extracting method, and establishing a known category—sampling image—feature point correspondence, where N is a natural number greater than 1, and each category comprises at least one sampling image; a cluster analyzing step (S 2 ) of performing cluster analysis on all of the feature points extracted using a clustering algorithm, and dividing the feature points into N subsets; an object category determining step (S 3 ) of determining an object category C n for each of the subsets; and a common feature acquiring step (S 4 ) of acquiring common features among the images in each object category C n with a search algorithm, where C n is the n th object category, and n is a positive integer no more than N.