Abstract: Software system has being faced challenge such as change of user requirements, software resources and system context environment, so software rectuirements must support sustainable evolution. Reflection mechanism has been successfully applied in the realm of the runtime management and dynamic evolution of software systems, but scarcely applied in the evolution of requirements specification. I}his paper proposed an approach which supports the evolution of OWL-S requirements specification based on reflection mechanism. Rectuirements analyst can implement the evolution of OWL-S requirements specification through describing and reasonably using the metes information of OWL-S requiremenu specification. By use of this approach analyst can effectively manage the requirements change and finish the evolulion task of recauirements specification through the controlled and orderly manner.

Key words: Requirement evolution, Reflection, OWL-S