An information processing device includes: a user information obtaining unit configured to obtain information relating to data of content that a user has used; a meta information obtaining unit configured to obtain content meta information corresponding to content that the user has used; a first vector generating unit configured to generate a first user preference vector with each of the obtained content meta information as elements thereof; a second vector generating unit configured to generate a second user preference vector wherein the generated first user preference vector is analyzed and the number of elements of the first user preference vector is compressed; and a user identifying unit configured to identify a user corresponding to a second user preference vector having a high similarity to a second user preference vector determined beforehand from multiple second user preference vectors.