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.