CET-6 certificate is necessary. If you want to do foreign trade, you need an export license. Unless you want to be a customs broker, you don't need to take the customs broker's card. However, most customs declarers have technical secondary school education, so it is not necessary to be a customs declarers when they come out of college. In fact, the most important thing for companies to recruit people is to look at the CET-6 certificate. There are also international trade, correspondence, business oral english, document making and other professional knowledge. In fact, many certificates are of little use. I'm just in foreign trade.