The decision making system of robot soccer is a kind of knowledge system. A Six step Reasoning Model is established by formalizing its expert knowledge and decision making process. Furthermore, many other models can be considered as mutation and evolution of the Six step Reasoning Model. The decision making system of robot soccer is a kind of knowledge system. A Six step Reasoning Model is established by formalizing its Expert knowledge and decision making process. Furthermore, many other models can be considered as mutation and evolution of the Six Step Reasoning Model.