Abstract.Replica management has become a hot research topic in storage systems. This paper presents a dynamic replica management strategy based on response time, named RTRM. RTRM strategy consists of replica creation, replica selection, and replica placement mechanisms. RTRM sets a threshold for response time, if the response time is longer than the threshold, RTRM will increase the number of replicas and create new replica. When a new request comes, RTRM will predict the bandwidth among the replica servers, and make the replica selection accordingly. The replica placement refers to search new replica placement location, and it is a NP-hard problem. Based on graph theory, this paper proposes a reduction algorithm to solve this problem. The simulation results show that RTRM strategy performs better than the five built-in replica management strategies in terms of network utilization and service response time.