Component specification languages in consideration of reuse are essential factor in classification, verification and retrieval of components. A number of legacy specification languages have already been used, however, they are complex and include many necessary elements in the specification for implementation. In this paper, we present XML-based component specification and software architecture specification language to solve these problems of legacy specification languages. The presented specification languages consist of component specification, which is composed of signature specification, interface specification and message specification, and software architecture specification providing graphical notations and textural notations. Component specification supports component retrieval with behavioral match and black-box reuse of component. In addition to this, it improves the efficiency of retrieval and document management with XML-based component specification. Software architecture specification supports the structural reuse of architecture, which is white-box reuse, through mesage-based architecture specification.