Abstract: The paper proposed a grouping adaptive multi-tree RFID anti-collision algorithm which divide the tags into many group based on the comprehensive analysis of variety tree-based algorithm,the tags is handled as group,the number of responding tags is reduced in the one time,thereby the probability of collision is reduced,in the same group,dynamic or dynamic quad-tree search is selected automatically according to the collision factor with using back strategy,simulation results show that the algorithm has improved greatly on the average number of queries and the amount of data transmission compared to other algorithms.