Facing the increasing competitive environment of globalization, companies are forced to make careful decisions so as to get the competitive advantage. The analytic hierarchy process (AHP) method has be proposed and popularly applied in many disciplines over three decades. In the past, many scholars also developed various improved methods such as Delphi AHP, fuzzy AHP, or Analytic Network Process (ANP) to enhance the decision quality. However, all the current AHP related methods have no function to provide enough reference information and a friendly environment to support the decision makers. Recently, Knowledge Management (KM) has attracted a great deal of interest in industry and academy. Therefore, in this paper, we proposed a KM-based AHP decision-making method to provide the questionnaire designer a guideline or reference and developed a decision-support web questionnaire system based on the knowledge chain model. A case study of selecting a 4-axis machine tool was illustrated the implementation and applicability of this method, a mold manufacturing company was invited as the survey objective. The method proposed in this research provides a different research direction and it is general in form to be applied for the other multi-criteria decision making cases.