The article presents the situation in the production and trade of onion in the years 2004-2014. There is shown the market structure and the dynamic and changes in trade in this vegetable and its preserves in the European Union market. Because of the Polish position in trade, the main attention was given to the exporters. There was conducted the trends analyze in export prices of fresh onions at the three major producers – exporters: Poland, Netherlands and Spain, based on monthly data. Also considered the Granger causality between the prices of these three countries.