With the raped transformation of science and technology, and the globalized circulation of money and information, most social economy in the world has stepped forward into service enterprise from manufacturing industry, and even more, is metamorphosing into the vague type of enterprise segmentation. This metamorphosis creates countless commerce chances. It also flourishes the operation mode based on knowledge and enforces the old type enterprise to adjust, to accept and to become ”enterprise based on knowledge” and ”learning enterprise.” Therefore, to go with this unavoidable tide, practicing the knowledge management (KM) becomes the most important task which enterprise management cannot ignore. In the following content, I first distinguished the definition and territory of knowledge and KM. Then I tried to draw up a practice plan of KM. Next, I analyzed how KM effected enterprise decision making and at last, observed the instances in Taiwan for verification.