Yakov Ivanovich Bulgakov (Russian: Яков Иванович Булгаков; 15 October 1743 – 7 July 1809) was a Russian diplomat best remembered as Catherine II's emissary in Constantinople in the 1780s. Of noble parentage, Bulgakov attended the gymnasium of the newly founded Moscow University. His class fellows included Ippolit Bogdanovich, Denis Fonvizin, and Grigory Potemkin. It was Bulgakov who was sent to notify Augustus III about the demise of Empress Elizabeth. A year later, he was dispatched to Vienna to inform Maria Theresa of Austria about the coup d'état that brought Catherine II to the throne.