Abstract: In order to make the tags be read fleetly and efficiently in RFID system, a novel dynamic framed slotted ALOHA anti-collision algorithm based on code division multiple access (CD-DFSA) is presented. Firstly, the design ideas of the novel algorithm are analyzed, then a novel algorithm model is constructed and the expressions of the optimal frame length and the number of estimated tags are deduced. Finally, simulation and comparative analysis is presented. Simulation results show that the CD-DFSA algorithm has a higher system throughput and uses fewer time slots for reading the same number of tags compared with the frame slotted ALOHA algorithm, dynamic framed slotted ALOHA algorithm and binary-tree algorithm.