Small Agricultural machinery (SAM) is applied widely in agriculture, forestry and stockbreeding. We focus the reconfiguration and Interoperability of the complex process of SAM product development, and propose a design architecture employing axiomatic design method and ontology information representation. In the proposed design process, product function decomposing and recomposing according to independent axiom of axiomatic design, all information of all design phases is expressed in ontology information model with XML language so that can be communicated among all engineers. A case study conducted in Small Agriculture Machinery (SAM) design helps to illustrate the proposed approach, it shows the proposed methods are feasible and reliable, lays a foundation of SAM product reconfigurable design system.