Quark is a fictional character in the television series Star Trek: Deep Space Nine, played by Armin Shimerman. A member of the ultra-capitalist Ferengi, Quark owned a bar on the promenade of Deep Space Nine.

The writing of the character softened considerably during the course of the series. Near the beginning, he was portrayed as highly immoral, and allowed nothing to stand in the way of profit. He was therefore occasionally mixed up in highly illegal activities. However, Quark gradually became a more appealing character, who, although never losing his greed, could be counted on to do what was right.

Quark's brother Rom succeeded Zek as Grand Nagus, and his nephew Nog was the first Ferengi in Starfleet.