James Luther "Luke" Sewell (January 5, 1901 – May 14, 1987) was an American professional baseball player, coach, and manager. He played in Major League Baseball as a catcher for the Cleveland Indians (1921–1932, 1939), Washington Senators (1933–1934), Chicago White Sox (1935–1938), and the St. Louis Browns (1942). Sewell batted and threw right-handed. He was regarded as one of the best defensive catchers of his era.

He spent 10 seasons playing with his brother Joe Sewell, a Hall of Fame shortstop. He had another brother named Tommy Sewell, who had one at-bat with the Chicago Cubs.

Sewell managed the Browns from 1941 to 1946, initially as a player-manager. The Browns won the American League pennant in 1944. He later managed the Cincinnati Reds from 1949 to 1952

Born in the rural town of Titus, Alabama, Sewell grew up wanting to play baseball. He attended Wetumpka High School and graduated from the University of Alabama where, he played for the Alabama Crimson Tide baseball team as an infielder. He was linked to the Cleveland Indians because his brother Joe Sewell became their starting shortstop in 1920. When Cleveland scout Patsy Flaherty signed Sewell, he insisted that he play as a catcher. He began the 1921 season with the Columbus Senators in the American Association but, after only 17 minor league games, Sewell made his major league debut with Cleveland on June 30, 1921.

Sewell served as a reserve catcher, working behind Steve O'Neill until the 1923 season when O'Neill was injured in an auto accident. Sewell then played in a platoon role alongside Glenn Myatt, in which the left-hand hitting Myatt played the team's home games at League Park due to its 290-foot distance to the right field fence, while Sewell played the team's road games. Sewell eventually took over as the Indians number one catcher in the 1926 season, due to his superior defensive skills. He finished the year with only a .238 batting average but led the American League catchers with 91 assists.

In 1927, Sewell had a breakout year, hitting for a career-high .294 batting average with 27 doubles, 53 runs batted in (RBI), and scored 52 runs. Sewell questioned Babe Ruth's integrity in a game on June 11, 1927. He demanded that umpires check Ruth's bat after he clouted two straight home runs off Garland Buckeye. Although he led the league's catchers with 20 errors, he also led the league with 119 assists and 71 baserunners caught stealing. Despite the fact that Cleveland finished the season in sixth place, Sewell ranked ninth in voting for the 1927 American League Most Valuable Player Award. In 1928, he once again led the league's catchers with 117 assists and 60 baserunners caught stealing and ranked 12th in voting for the 1928 American League Most Valuable Player Award.

In 1933, Sewell was traded to the Washington Senators for catcher Roy Spencer. Sewell posted career-highs with 125 hits and 30 doubles, as the Senators, under first-year player-manager Joe Cronin, won 99 games to clinch the American League pennant by nine games over the New York Yankees. During an April game against the Yankees, Sewell made an odd double play. Lou Gehrig and Dixie Walker were on base when Tony Lazzeri hit a ball to deep right field. Gehrig hesitated as he waited to see if the ball would be caught, before heading towards home plate with Walker right behind him. Sewell caught right fielder Goose Goslin's throw and tagged both runners out with one sweeping motion. Cronin credited Sewell as a major factor in helping the Senators' pitching staff. The Senators lost to the New York Giants in the 1933 World Series. In what would be his only postseason appearance as a player, Sewell posted a .176 batting average (3 for 17), with one stolen base, one run scored, and one RBI during the five-game series.

Sewell began the 1934 season with a hand injury and didn't play his first game until June 13. Two weeks later, he was struck in the head and knocked unconscious by a pitch thrown by St. Louis Browns pitcher, Bump Hadley. Sewell ended the season with a .237 batting average.