The purpose of this study is to analyze the impacts of the July Package, the conclusion of the new WTO negotiations wrapped up in July 2004, on Taiwan's economic development. We focus, in particular, on the issue of agricultural market access. A multiregional, multi-sector CGE model-Global Trade Analysis Project (GTAP)-is used to do the quantitative analysis on the aspects of macro-and micro-economy, as well as national welfare. The empirical results show that Taiwan's real GDP will slightly increase, though the national welfare decreases due to the deterioration of the terms of trade. There will be significant restructuring in the agricultural sector, within which the ”other food products” and the ”animal and meat products” are the most affected areas.