Gaming law is generally the law that applies to the gaming or gambling industry, including casinos, lotteries, horse racing, dog racing, sports betting, card games, table games, social gambling, bingo, raffles, slot machines, scratch tickets, etc. Gaming law includes state and federal statutes, rules, and regulations—and legal principles from traditional areas of law, such as contract law, administrative law, constitutional law, criminal law, and regulatory law. For example, the federal statute prohibiting illegal gambling businesses is located at 18 U.S.C. §1955.

In Montana (MT), gaming law encompasses the regulation of various forms of gambling, including casinos, lotteries, sports betting, and more. The Montana Department of Justice's Gambling Control Division oversees the enforcement of the state's gambling laws. Casinos are legal on Native American reservations and are regulated by tribal gaming commissions in accordance with federal law, specifically the Indian Gaming Regulatory Act. The state lottery is operated by the Montana Lottery Commission. Sports betting was legalized in Montana in 2019, and the state allows for wagering through sportsbooks licensed by the Montana Lottery. Social gambling, bingo, and raffles are permitted under certain conditions, and charitable organizations can conduct gaming events with the proper licenses. Slot machines and other electronic gaming devices are also regulated and are allowed in licensed establishments. The federal statute 18 U.S.C. §1955, which prohibits illegal gambling businesses, applies in Montana as it does nationwide, working in conjunction with state laws to govern the legality of gambling operations.