Vern Jarl Olsen (March 16, 1918 – July 13, 1989) was an American professional baseball player, a left-handed pitcher who appeared in 112 Major League games for the Chicago Cubs (1939–42; 1946).

He served in the United States Navy in the Pacific Theater of Operations during World War II[1][2][3] and missed three full seasons at the peak of his career.

After four scoreless relief appearances in the closing days of the 1939 season, Olsen then made the Cubs' 1940 roster and, after more success as a reliever, began taking a regular turn in the Chicago starting rotation in July 1940.

On August 22, he threw a complete-game, two-hit shutout against the Brooklyn Dodgers, contributing two hits to the winning cause himself as the Cubs won, 5–0, at Wrigley Field.

[5] During his Major League career, Olsen gave up 547 hits and 192 bases on balls in 516 innings pitched, with 201 strikeouts, 23 complete games, seven shutouts and two saves.