This study used the dynamic ARIMA transfer function model to identify, diagnose and estimate the model based on yearly time series data from 1975-96. From the dynamic perspective the empirical results show that inward FDI had had a positive impact on Taiwan's RCA, and it was still true while inward FDI was lagged one period, though the influential power was marginal. Nevertheless outward FDI had had a negative effects on Taiwan's RCA from a static viewpoint. The implication is that outward FDI produced the replace export effect and adverse import effect of the intra-industry trade behaviors. The explanatory variable ”the par earning of unit product exported” was also significantly positively related to RCA, and the impact was more powerful than that of the other explanatory variables.