The following are the baseball events of the year 1945 throughout the world.  

Champions

Major League Baseball

• World Series: Detroit Tigers over Chicago Cubs (4-3)
• All-Star Game cancelled due to flight restrictions. However, inter-league games were played during the All-Star break.

Other champions

• Negro League World Series: Cleveland Buckeyes over Homestead Grays (4-0)
• Negro League Baseball All-Star Game: West, 9-6
• All-American Girls Professional Baseball League: Rockford Peaches

Awards and honors

• Most Valuable Player
  • Hal Newhouser (AL) - P, Detroit Tigers
  • Phil Cavarretta (NL) - 1B, Chicago Cubs
• The Sporting News Player of the Year Award
  • Hal Newhouser - P, Detroit Tigers
• The Sporting News Most Valuable Player Award
  • Eddie Mayo (AL) - 2B, Detroit Tigers
  • Tommy Holmes (NL) - OF, Boston Braves
• The Sporting News Pitcher of the Year Award
  • Hal Newhouser (AL) - Detroit Tigers
  • Hank Borowy (NL) - Chicago Cubs
• The Sporting News Manager of the Year Award
  • Ossie Bluege - Washington Senators

MLB Statistical Leaders

Major League Baseball final standings

American League final standings

National League final standings

Negro League Baseball final standings

Negro National League final standings

Events

January-March

April-June

• May 17 - For the fourth time in four days, every American League game was postponed due to rain.

July-September

• August 1 - Mel Ott hits the 500th home run of his major league career.
• August 4
  • World War II amputee Bert Shepard pitches in a game for the Washington Senators.
    
  • Tom McBride of the Boston Red Sox ties a major league record with 6 RBI in the 4th inning of a game with the Washington Senators.
    
  • Senators pitcher Joe Cleary becomes the last native of Ireland to appear in a major league game.
• September 9 - Cleveland Indians first baseman Mickey Rocco leads the way to a doubleheader sweep of the New York Yankees with two home runs, two doubles, and two singles. A crowd of 72,252 is on hand at Yankee Stadium to see their team lose 10-3 and 4-3.
• September 9 - In the second game of a double-header Dick Fowler pitches a no-hitter as the Philadelphia Athletics defeat the St. Louis Browns, 1-0.
• September 29 - Chicago Cubs catcher Paul Gillespie homers in his final major league at bat. In 1942 he homered in his first major league at bat. He is the only the second player in MLB history to do both. John Miller is the second.

October-December

• October 10 - The Detroit Tigers defeat the Chicago Cubs, 9-3, in Game 7 of the World Series to win their second World Championship, four games to three. To date, the Cubs have not won another National League pennant and have not won the World Series since 1908, these are the longest such droughts in the history of baseball.
• October 23 - Jackie Robinson is signed by the Dodgers; he is later assigned to the Montreal Royals for the 1946 season.

Date Unknown

• The Mexican Winter League is born with the name Liga Invernal de Sonora

Births

January-March

• January 3 - Larry Barnett
• January 7 - Tony Conigliaro
• January 25 - Wally Bunker
• January 29 - Dick Mills
• February 11 - John Paciorek
• February 12 - Don Wilson
• March 11 - Dock Ellis
• March 12 - Horacio Piña

April-June

• April 2 - Mike Kekich
• April 2 - Reggie Smith
• April 2 - Don Sutton
• April 11 - Mike Kilkenny
• April 15 - Ted Sizemore
• May 3 - Davey Lopes
• May 4 - Rene Lachemann
• May 26 - Al Yates
• May 29 - Blue Moon Odom
• June 25 - Dick Drago

July-September

• July 1 - Billy Rohr
• July 7 - Chuck Goggin
• July 7 - Bill Melton
• July 10 - Hal McRae
• July 29 - Roy Foster
• August 6 - Andy Messersmith
• August 15 - Duffy Dyer
• August 21 - Jerry DaVanon
• September 8 - Ossie Blanco
• September 13 - Rick Wise
• September 16 - Ed Sprague
• September 25 - Steve Arlin
• September 26 - Dave Duncan

October-December

• October 1 - Rod Carew
• October 15 - Jim Palmer
• October 27 - Mike Lum
• November 3 - Ken Holtzman
• November 19 - Bobby Tolan
• November 20 - Jay Johnstone
• November 20 - Rick Monday
• December 6 - Larry Bowa
• December 12 - Ralph Garr
• December 19 - Geoff Zahn

Deaths

• May 27 - Walter Carlisle, 63, outfielder for the Boston Red Sox, who entered the records books as the only outfielder ever to make an unassisted triple play in organized baseball, while playing in the Pacific Coast League
• June 18 - Sid Mercer, 64, sportswriter for New York newspapers since 1905, previously in St. Louis; also an official with the St. Louis Browns from 1903-05
• June 29 - Clarence Winters, 45, pitcher for the 1924 Boston Red Sox
• August 7 - Bobby Veach, 57, left fielder for the Tigers who batted .310 lifetime, led AL in RBI three times and doubles twice
• September 13 - Cy Blanton, 37, All-Star pitcher who played for the Pirates and Phillies in the 1940s and twice led National League in shutouts
• September 29 - George Van Haltren, 79, center fielder, primarily with the New York Giants, who batted .316 lifetime and ranked sixth all-time in both hits (2500+) and runs upon retirement; led NL in triples and steals once each, also won 40 games as pitcher, including a 6-inning no-hitter
• October 16 - Hack Eibel, 51, versatile player for the 1912 Cleveland Naps and 1920 Boston Red Sox
• December 27 - Hugh Fullerton, 72, Chicago sportswriter who helped break the story of the Black Sox scandal; an early advocate of the value of statistics, he first gained wide attention for correctly predicting the White Sox' upset of the Cubs in the 1906 World Series, even getting right the winner of each game and the day of a rainout