1. An image retrieving apparatus for retrieving an image similar to a predetermined query image out of subject videos for retrieval, comprising: a frame feature vector extracting means for extracting a feature vector of at least a part of frames included in said subject videos for retrieval, and for outputting said extracted one as a frame feature vector; a frame feature vector storing means for storing the frame feature vector outputted by said frame feature vector extracting means; an image feature vector extracting means for extracting a feature vector of said query image and for outputting said extracted one as an image feature vector; a similarity calculating means for comparing the frame feature vector stored in said frame feature vector storing means with the image feature vector outputted by said image feature vector extracting means to thereby calculate a similarity of both vectors; a frame feature vector integrating means for integrating frame feature vectors out of those stored in said frame feature vector storing means that satisfy a predetermined condition on similarity into at least one group; and, a similar image selecting means for selecting at least one frame feature vector of a highest similarity out of the group integrated by said frame feature vector integrating means, whereby images having the frame feature vector that is selected by said similar image selecting means is presented as a result of retrieval.