The invention discloses a radio frequency identification (RFID) safety authentication method. The thought of dynamically selecting an encryption algorithm is introduced, namely a plurality of encryption algorithms which are safe and easy to realize on hardware are adopted and serve as an algorithm bank. One of the encryption algorithms is selected at one time to encrypt and decrypt through a random function. Meanwhile, a mechanism of double-key and triple authentication is adopted so that the method has high safety performance, realizability of the hardware can be guaranteed, and safety of a system can be greatly improved through diversity of the algorithms. The RFID safety authentication method can be realized without configuration of high hardware resources which serve as support, offer high safety and solve the problem that a high safety encryption algorithm can not be operated on a low cost label.