The progressive processes of globalisation, integration and liberalisation of economies are the reason for which the competitiveness of economic entities is increasingly analysed in the context of their links with the international market. One of the ways to assess competitiveness is to analyse the comparative (relative) advantage in trade in products of a given economic sector. The objective of the article is to assess the comparative advantage in Polish foreign trade in food and non-food products, both in total Polish trade and with European Union Member States. The studies used the RTA relative trade advantage index. The data source was the WITS-Comtrade commercial database. The studies show that, in the years 2004-2017, there was a rapid development of Polish foreign trade in food products, in particular with the EU, resulting in a high trade surplus. Trade in non-food products grew more slowly, and the trade balance was negative. It is shown that Poland had a comparative advantage and was competitive on the world market (also on the EU market) in trade in these products, but did not have such an advantage in total trade in non-food products. The results obtained indicate international competitiveness of the Polish food sector and its large importance for national trade and payment balance.