Abstract: R-tree is incapable of managing spatial objects in concurrent environment.We proposes the CQR-tree(concurrent quad-tree & R-tree) to satisfy this situation,which is easy to integrate with existing R-tree systems.Firstly,we point out the limitation of R-tree in concurrent environment and the limitation of the R-link tree in the special system.Secondly,we introduce the CQR-tree to solve the problem.Thirdly,we list the algorithms of the CQR-tree,including insert,add,and delete operators,and the query strategy.Then,some experimental results confirm that the proposed CQR-tree performs well in concurrent environment.