William Bertrand Busnach (7 March 1832, Paris – 20 January 1907, Paris) was a French dramatist. Busnach was a nephew of the composer Fromental Halévy. His father was associated with David Ben Joseph Coen Bakri, to whom France was indebted to the amount of some twenty-odd million francs for provisions furnished to Napoleon Bonaparte in Egypt. The lawsuit lasted for more than fifty years, and Busnach and his partner were not paid in full at the end. The elder Busnach, an Algerian Jew, became a naturalised Italian in the time of the Deys, and was the first interpreter of the French army. He established himself in Paris in 1835.