Abstract: In the aspect-oriented programming，aspect weaving is the implementation of weaving system concerns，and the weaving strategy will affect the execution efficiency，weaving granularity and modularity degree of software system.According to the requirements of aspectual component assembling platform and computing on demand middleware platform，this paper proposes a kind of Dynamic Aspect Weaving model—DAWeaver.It uses BCEL to modify class file，calls aspect component reflectively through aspect container，and supports dynamic weaving.In the end，this paper gives a prototype system and analyzes the weaved system’s performance.