International trade patterns are mainly divided into inter industry trade and intra industry trade, and along with the development of global and regional economic integration process, trade patterns gradually change from inter industry to intra industry. In this paper, the Lafay Index of Taiwan’s ten kinds of products according to SITC is calculated by using the import and export data from the year of 1998 to 2015, and the results show that inter industry trade is the main pattern of Taiwan’s international trade. Intra industry and inter industry trade are based on product differentiation and scale economy, production efficiency and factor endowment differences respectively. We further construct Trade Pattern Deviation Index (H Index) based on the RSCA Index and TC Index, it’s found that the overall net export capacity of Taiwan is higher than the level of comparative advantage, and thus the deviation tendency of trade pattern is positive.