Anvaing Castle (French: Château d'Anvaing) or Château de Lannoy is a historic residence in the village of Anvaing in the municipality of Frasnes-lez-Anvaing, province of Hainaut, Wallonia, Belgium.

The site of the Château d'Anvaing has been occupied by a castle since the time of the First Crusade.

Stéphanie de Lannoy, Hereditary Grand Duchess of Luxembourg, grew up in the castle.

The castle is chiefly notable as the place in which the Belgian capitulation was signed on 28 May 1940, during the Battle of the Lys.

In celebration, a German officer fired a gunshot into the ceiling which is still present.