Ryan "The Beast" Riess (born 1990) is an American professional poker player. He is best known for winning the 2013 World Series of Poker Main Event.

Riess graduated from Michigan State University with a Hospitality degree. His first tournament cash came in October 2012, when he took 2nd place at the World Series of Poker Circuit main event in Hammond, Indiana for $239,063. In the following few months he had several cashes in smaller events throughout the United States. Riess first played the WSOP in 2013, cashing in 3 preliminary events with a best finish of 11th in a $1,000 No Limit Hold'em event. Playing in his first WSOP Main Event, he made the November Nine in 5th chip position with 25,875,000. After eliminating 4 players at the final table, Riess entered heads-up against Jay Farber with a nearly 20 million chip deficit. After 90 hands of heads-up play, Riess' A♥ K♥ defeated Farber's Q♠ 5♠ to win the championship bracelet and $8,361,570.