Dennis Dale McLain (born March 29, 1944), commonly known as Denny McLain, was an American professional baseball player. He is noted for being the last major league pitcher to win 30 or more games during a season.

McLain broke into the major leagues in 1963. His first good season came in 1965, when he posted a 2.61 ERA and a 16-6 record. He would remain one of the top pitchers in Major League Baseball until 1969. His 1968 season was a remarkable one, as he went 31-6, was an all-star, won the Cy Young Award, won the A.L. Most Valuable Player Award, and was on the World Series-winning Detroit Tigers. McLain's World Series was not stellar, as he lost games 1 and 4 to Bob Gibson and the St. Louis Cardinals, but won the crucial Game 6, with the Tigers trailing 3 games to 2.

McLain's baseball career was short-circuited by associations with gamblers; he was suspended for most of the 1970 season for this behavior, and left the majors in 1972 at the age of 28. His post-baseball career has included imprisonment for drug trafficking and embezzlement.

McLain was a three-time all-star and won the Cy Young Award twice in his career (1968, and 1969, when he shared the award with Mike Cuellar). His lifetime record includes a record of 131-91, an ERA of 3.39 and 1282 strikeouts in 1886 innings pitched.