The invention relates to a lightweight no-service type RFID (radio frequency identification) safe search protocol. The protocol uses multiple tag collision for protecting the privacy of a target tag; a loose timestamp and a one-way Hash function are used, so that the safety problem possibly occurring to a data link between an RFID reader and the tag is effectively solved; and under the condition that no background server exists, the HASH function which can be realized through a passive tag is adopted, so that safe search and bidirectional authentication to the tag are guaranteed, and excellent characteristics of fast search and safety certificate are realized. Common active and passive attacks in a wireless link can be effectively resisted. The lightweight no-service type RFID safe search protocol is ingenious in structure and wide in application environment, and has a high safety level and privacy level.