The small and medium-sized enterprises (SMEs) were once the most important driving force and main contribution to foreign exchange for economic development in Taiwan. However, with the change of international trading environment and domestic production environment, it makes the cooperative patterns of SMEs change too. This paper probes into the theory and industry's case study, and finds that under the fast progress of technology and the wave of globalization, the cooperative behaviors of enterprises have a clear tactical intention with increased and closer cooperation. The evolution of cooperative patterns of Taiwan's SMEs goes through three stages: In the first stage, SMEs depend on the outsourcing orders from foreign enterprises to produce low technology products in the industry networks; The second stage, SMEs cooperate with big enterprises in center-satellite factory systems and upgrade production technology and quality; The third stage, SMEs cooperate with each other to build up independent marketing ability and brand names. The new cooperative pattern offers government a new direction of SMEs policy.