1. A method for pushing recommended friends to a user on a social networking site, wherein the method comprises: automatically analyzing, by a first social networking site, usage information of each user on the first social networking site to obtain feature information of each user on the first social networking site, wherein the usage information of the each user on the first social networking site refers to information comprising personal information, habits, hobbies, and a current state shown by the each user during using the first social networking site, and the feature information of the each user on the first social networking site comprises hobbies, occupation and location of the each user on the first social networking site; wherein automatically analyzing the usage information of the each user on the first social networking site to obtain feature information of the each user on the first social networking site comprises: obtaining the each user's location by analyzing the each user's registration information; obtaining the each user's hobbies according to the interactions between the each user with other people on the first social networking site; and obtaining the each user's occupation according to information published by the each user; receiving, by the first social networking site, usage information of each user on a second social networking site cooperating with the first social networking site, wherein the usage information of the each user on the second social networking site refers to information comprising personal information, habits, hobbies, and a current state shown by the each user during using the second social networking site; automatically analyzing, by the first social networking site, the usage information of each user on the second social networking site cooperating with the first social networking site to obtain feature information of each user on the second social networking site, wherein the feature information of the each user on the second social networking site comprises hobbies, occupation and location of the each user on the second social networking site; wherein automatically analyzing the usage information of the each user on the second social networking site to obtain feature information of the each user on the second social networking site comprises: obtaining the each user's location by analyzing the each user's registration information; obtaining the each user's hobbies according to the interactions between the each user with other people on the second social networking site; and obtaining the each user's occupation according to information published by the each user; matching, by the first social networking site, feature information of a user on the first social networking site with feature information of other users on the first social networking site and with feature information of other users on the second social networking site; obtaining, by the first social networking site, based on the matching, matching goodness-of-fit values of feature information between the user and the other users; determining, by the first social networking site, users corresponding to matching goodness-of-fit values which are greater than a preset goodness-of-fit value as matching users of the user; sending, by the first social networking site, a friend recommendation information to the user, wherein the friend recommendation information comprises information of each matching user; and sending, by the first social networking site, a friend recommendation information to the each matching user, wherein the friend recommendation information comprises information of the user.