The Prohibition Party (PRO) is a political party in the United States best known for its historic opposition to the sale or consumption of alcoholic beverages. It is the oldest existing third party in the US. The party was an integral part of the temperance movement. While never one of the leading parties in the United States, it was once an important force in the politics of the United States during the late 19th century and the early years of the 20th century. It has declined dramatically since the repeal of Prohibition in 1933. The party earned only 643 votes in the 2008 presidential election. The Prohibition Party advocates a variety of socially conservative causes, including "stronger and more vigorous enforcement of laws against the sale of alcoholic beverages and tobacco products, against gambling, illegal drugs, pornography, and commercialized vice."

The Prohibition Party was founded in 1869. Its first National Committee Chairman was John Russell of Michigan. It succeeded in getting communities and also many counties in the states to outlaw the production and sale of intoxicating beverages.