Reconfigurable systems, composed by many components, can exhibit different function caused bycomponent combinations and alternations. This paper focuses on the lack of methodology used in describing formalmodel and reconfigurable attributes of the reconfigurable system. The paper also focuses on the abstracts anddescribes the attributes and the behaviors of reconfigurable system and the component combination andreconfigurable method by an algebraic method. By understanding the component combination of an operation that isa new idea and extending the calculus in algebraic process, some component combination operators are defined.Next, a formal algebraic model of reconfigurable system is proposed. Based on this model, some reconfigurableattributes are analyzed and a few reconfigurable nomal formats are proposed. All above viewpoints construct thetheoretical footstone for designing reconfigurable system. Finally, a case study is introduced to explain how theabove algebraic model can be used.