Mardi Gras Casino & Resort opened as Tri-State Greyhound Park in May 1985. Over the years, the facility in Nitro was expanded and improved as additional forms of gambling became legal in West Virginia.

The track installed 400 video machines in 1994 under a license granted by the West Virginia Lottery Commission. The facility underwent a major expansion that was completed in December 2002. The $12 million Mardi Gras addition included a new simulcast betting lounge, a full-service restaurant, a cafe, four bars, two entertainment stages, a "high-rollers" section, and a conference area. In 2007, the legislature authorized local option voting on allowing an expansion of gambling at the state’s racetracks. In August 2007, Kanawha County voters narrowly approved table games after a contentious campaign. The table games now offered include blackjack, poker, roulette, and others.

In 2010, Tri-State Casino & Resort changed its name to Mardi Gras Casino & Resort, and the facility now has 90,000 square feet of gambling and more than 1,200 slot machines. Greyhound racing continues at the facility, as well. The resort, which is owned by the Michigan company Hartman & Tyner, opened a 150-bed hotel in July 2010.