A content identification method and system, and a secure content identification mechanism (SCIDM) client and server are provided. The content identification method includes: selecting an identification mechanism for a content to be identified; extracting identification information of the content to be identified corresponding to the selected identification mechanism; and sending a first content identification request, in which the first content identification request contains the selected identification mechanism and the identification information, and is adapted to request an SCIDM server to identify an attribute of the content to be identified by using the identification mechanism and according to the identification information. Thus, a load of a content identification system is reduced, and an efficiency of content identification is improved.