Yekaterina Alexeyevna Sinyavina (died 1784) was a Russian composer and pianist. A cembalo concerto by Giovanni Paisiello was probably first performed at the court of Catherine II in 1781 with Sinyavina as soloist. She served as a lady-in-waiting and composer at the court, married Count Simon Romanovich Vorontsov and died in St. Petersburg.[1][2]