Mardi Gras Casino & Resort opened as Tri-State Greyhound Park in May 1985. Over the years, the facility in Nitro has been expanded and improved as additional forms of gambling have become 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. The facility now has a 150-room hotel, 900 slot machines, more than 20 table games, a live music lounge, sports wagering, meeting and banquet services, restaurants, an indoor heated pool and fitness facilities, and a gift shop. Greyhound racing continues at the facility, as well.

The resort was acquired by Delaware North in 2018.