Abstract: This paper firstly depicts the import and export conduction path of enterprises with trade policy uncertainty and the bilateral phase deviation between China and the United States, thenit quantitatively checks the import and export effects of Sino-U.S. trade policy uncertainty through the SV-TVP-FAVAR model from the triple perspectives of time distribution, phase deviation and country impact differences. The results show that: firstly, trade policy uncertainty has multiple import and export transmission paths for enterprises, and the cross-country cross-conduction characteristics are obvious;the Sino-US trade policy uncertainty has not only a long-term“consistent”trend in the early stage of the sample, and also a short-term trend of“deviating”trend in the later stage of the sample. Secondly, the uncertainty of Sino-US trade policy presents the characteristics of negative impact of enterprises' import and export heterogeneity; the negative spillover effect of Sino-US trade policy uncertainty is differentin different periods, and the negative spillover effect has not weakened in recent years. Thirdly, the different deviating stages of the uncertainty of Sino-US trade policy will lead to different import and exporteffects of enterprises with Sino-US trade policy uncertainty;during the expansion period of Sino-US bilateral deviation, the import and export effect of the enterprises with Sino-US trade policy uncertainty is stronger than that during the stable period,the uncertainty of China's trade policy has always been the main factor affecting the import and export of Chinese enterprises. The above analysis has important guiding significance for all walks of life to understand the trend and fluctuation characteristics, the bilateral deviation and the country-specific impact differencesof China-US trade policy uncertainty, so as to avoid the “Thucydides Trap”.

Key words: trade policy uncertainty, bilateral deviation, import and export of enterprises, dynamic shock