Anti-collision　is　a　key　technology　in　systems　and　applications　in　which　Radio　Frequency　Identification　(RFID)　is　used　since　it　determines　the　efficiency　of　RFID　tag　identification.　Although　binary-tree　search　algorithms　can　effectively　resolve　collisions,　they　may　not　be　very　efficient　in　systems　with　a　large　number　of　RFID　tags.　In　this　paper,　we　propose　a　new　flat-tree　anti-collision　algorithm　and　show　that　the　proposed　algorithm　is　more　suitable　for　resolving　collisions　involving　a　massive　number　of　RFID　tags.　Through　analysis　and　experiment,　we　show　that　the　flat-tree　algorithm　outperforms　the　binary-tree　search　algorithms　when　the　number　of　RFID　tags　reaches　a　massive　scale,　i.e.,　exceeds　a　certain　number.　©　(2013)　Trans　Tech　Publications,　Switzerland.