Tournai or Tournay is a city and municipality of Wallonia located in the province of Hainaut, Belgium. It lies 85 kilometres (53 miles) southwest of Brussels on the river Scheldt. Tournai is part of Eurometropolis Lille–Kortrijk–Tournai, which had 2,155,161 residents in 2008.

Tournai is one of the oldest cities in Belgium and has played an important role in the country's cultural history. It was the first capital of the Frankish Empire, with Clovis I being born here.

Tournai is located in the Picardy Wallonia and Romance Flanders region of Belgium, at the southern limit of the Flemish plain, in the basin of the River Scheldt (Escaut in French, Schelde in Dutch). Administratively, the town is part of the Province of Hainaut, itself part of Wallonia. It is also a municipality that is part of the French-speaking Community of Belgium. Tournai has its own arrondissements, both administrative and judicial.