Taiwan PC OEM industry has developed almost 20 years. In these years, Taiwan PC OEM industry made large output volume and had a huge market share during these 20 years but the profit kept falling oppositely. Facing this repeating situation, the research use system thinking approach to construct the system structure which focus on the relationships between OEM firms and brand firms in notebook industry in order to find out the reason why OEM firms' profits squeeze continuously. First of all, this research analyze the interaction between key factors in the systems then depict structure of the issue. Furthermore, according to the system structure of the notebook industry, the research described how the main schemas changed time by time, and analyze the different forces that squeeze OEM firms¡¦ profits. Finally, the research provided some opinions on improving this profits squeezed situation.