Antoinette de Merode (Antoinette Ghislaine; 28 September 1828 – 10 February 1864), Princess of Monaco, was born in Brussels as the daughter of Count Werner de Merode and his spouse Countess Victoire de Spangen d'Uyternesse (1797–1845).
She married on 28 September 1846 in Brussels to Charles III, Prince of Monaco. It was a double wedding with her older sister, Louise. Thanks to her generous dowry Prince Charles III was able to finance the embellishment of Monte Carlo in order to attract wealthy tourists to the principality. She acquired for herself the Château de Marchais which is still the property of the Grimaldi family today. From 1856 until her death in Monaco she was the Princess consort of Monaco. She gave birth to Albert I, Prince of Monaco.