The purpose of this paper is to study the contemporary Taiwan-China economic integration which is socalled "Cross-Strait Relation" through the investment behaviors to the mainland China of the Taiwanese enterprises, especially those of the business groups. From the end of the 20th century, their investment to mainland China has become more market-oriented rather than establishing "industrial bases" for export. China's economic development and its integration into the Pacific-Basin's economic dynamics have enabled its market to be more mature and induced Taiwanese business into the mainland drastically. The increse of the Taiwanese investment to mainland China is syncronized with the reorganization of business circumstance in Taiwan where the business groups have occupied more predominant role in its economy. Through this study, I would like to explain the causual relation between managemental reorganization and investment to mainland China by the business groups of Taiwan.