George Cosac (born 26 January 1968) is a former tennis player from Romania. He competed in doubles at the 1992 Summer Olympics, together with Dinu Pescariu, but the pair was eliminated in the quarter-finals. Cosac reached his highest singles ATP-ranking on 23 October 1995, when he became the number 265 of the world.
On 22 February 2013, he was elected president of the Romanian Tennis Federation.