Baron Emile-Ernest de Cartier de Marchienne (30 November 1871 in Schaerbeek, Belgium – 10 May 1946 in London, United Kingdom) was a Belgian diplomat. Emile de Cartier de Marchienne was Belgian Minister in the United States, China, the United Kingdom, Cuba, Haiti, and the Dominican Republic. Before that he had been the charge d'affaires in Brazil, Japan, China, and France.