Brexit makes EU economy facing many problems such as trading system, employment and labor job opportunities, inflation and investment between UK and EU. UK is an important trading partner for EU, because of its large economy. In EU economy, UK is considered as a main exporter that always exports products and services to EU leading to the increasing EU economic growth. Moreover, UK covers 5% of EU GDP because of their export to EU market. There are some EU members that face a big problem after Brexit succeeds including Ireland, Netherland, Belgium and Germany (Cathleen & Zhiyao, 2016). Those countries’ products are mostly imported to UK rather than other EU members. Germany’s export to UK accounts for $6,718,802 EUR million in January, 2017; while UK’s import to Germany has an average around $530,843.79 EUR million (Economics, n.d.). Therefore, Germany mostly depends on UK market. EU as a whole also gets affected, especially on manufacturing goods and technological products since UK is the main supplier for those products. In addition, Brexit will lower EU economic growth through decreasing the import of EU products into UK due to political obstacle between EU and UK. Moreover, UK will leave from the European single market and Custom Union. Which means that UK will impose the new tariff and quotas on EU products, because UK did not care much about EU rule on trading after Brexit. Single market and custom unions is the place that all the EU member can enjoy free from tariff and no quota limitation on flow of products into any EU members (Dominic & Lorna , 2017). All in all, Brexit makes EU facing many problems not only the trading issues between EU and UK, but also the FDI from UK investor into EU member states. As we know, trade is the main actor that can maintain the relation between EU and UK. If UK and EU are unable to trade with each other, EU will face bad consequences more than UK, because EU depends on UK rather than other EU member states. All those kinds of problem can only be solved through future negotiation between two countries.