As the frequency of trade interventions increases year by year,the risk of global trade frictions has been rising,seriously affecting the development of international trade.The multilateral round negotiation process of the WTO has been hindered,prompting more countries to sign FTA as an important path to achieve trade liberalization.China has also proposed building a high-standard free trade agreement network facing the globe.An analysis of trade friction data from the GTA database between 2009 and 2020 reveals that the number of trade interventions initiated by various countries increased gradually before 2020.However,the impact of the COVID-19 pandemic in 2020 intensified trade interventions by countries,with most of these aimed at trade protection.The United States is the country that has initiated the most trade frictions and China is the country that has encountered the most trade frictions.Countries that frequently initiate trade frictions are also prone to trade frictions from other countries,exhibiting a clear"club effect".The proportion and representativeness of standard trade remedy actions,such as anti-dumping,in trade frictions are decreasing year by year.By improving the calculation method of FTA vertical depth using the Deep Trade Agreement Database,both theoretical analysis and empirical research indicate that deep FTA can reduce the probability and frequency of bilateral trade frictions by establishing and improving dispute resolution mechanisms,narrowing down the gap in economic growth between countries,and establishing closer economic and trade cooperation relationships.Heterogeneity analysis of national characteristics shows that the mitigating effect of deep FTA is limited for trade frictions initiated by member countries of the"club";the increase in the number of bilateral FTAs weakens the mitigating effect of deep FTA,highlighting the"spaghetti bowl effect";and deep FTA can mitigate trade frictions brought by the Wassenaar Arrangement,thus serving as a useful tool to break the long-arm jurisdiction.Compared with existing studies,the types of trade frictions examined in this study are more diverse,covering not only non-tariff measures such as anti-dumping and technical barriers to trade(TBT)but also trade interventions such as tariff measures,investment restrictions,and intellectual property protection.By constructing vertical depth indicators to capture differences and dynamic changes in FTA provisions,the mitigating effect of deep FTA on bilateral trade frictions is investigated in comprehensive and systematic way.This study further clarifies the mechanism that deep FTA mitigate trade frictions and empirically validates possible mechanisms,including dispute resolution.The results provide important insights for China to reduce the risk of encountering trade frictions so as to adhere to expanding high-level opening up,to accelerate the implementation of the strategy of upgrading Free Trade Zone,and to build a high-standard free trade zone network facing the globe.