In an open and dynamic network environment, distributed software shows the characteristics of large-scale, loose aggregation and complex behavior, which needs dynamically monitor. Proposes a strategy-driven monitoring model in which AOP (Aspect Oriented Programming) aspects are selected by adaptive strategy. With dynamic weaving mechanisms, the monitor composed by the aspects can be added and deleted according to the change of monitor value in the running process of target system. Therefore the model is able to adapt procedures and current system conditions changing and dynamically adjust the monitoring intensity to keep a balance of monitoring load, so as to get best monitoring results and achieve dynamic monitoring purposes. Simulation results show that the design of the monitoring model is reasonable.