The following are the baseball events of the year 1990 throughout the world.
Major League Baseball
- World Series: Cincinnati Reds over Oakland Athletics (4-0); José Rijo, MVP
- All-Star Game, July 10 at Wrigley Field: American League, 2-0; Julio Franco, MVP
- Caribbean World Series: Leones del Escogido (Dominican Republic)
- College World Series: Georgia
- Japan Series: Seibu Lions over Yomiuri Giants (4-0)
- Little League World Series: San-Hua, Tainan County, Taiwan
Awards and honors
- Most Valuable Player
- Cy Young Award
- Rookie of the Year
- Manager of the Year Award
MLB Statistical Leaders
Major League Baseball final standings
|1st||Boston Red Sox||88||74||.543||--|
|2nd||Toronto Blue Jays||86||76||.531||2.0|
|7th||New York Yankees||67||95||.414||21.0|
|2nd||Chicago White Sox||94||68||.580||9.0|
|6th||Kansas City Royals||75||86||.466||27.5|
|2nd||New York Mets||91||71||.562||4.0|
|6th||St. Louis Cardinals||70||92||.432||25.0|
|2nd||Los Angeles Dodgers||86||76||.531||5.0|
|3rd||San Francisco Giants||85||77||.525||6.0|
|4th||San Diego Padres||75||87||.463||16.0|
- January 9 - Jim Palmer, a three-time American League Cy Young Award winner, and Joe Morgan, a two-time National League MVP, are elected to the Hall of Fame by the Baseball Writers Association of America in their first year of eligibility.
- July 10 - Six American League pitchers combine for a two-hitter and a 2–0 victory over the National League in a rain-delayed All-Star Game at Wrigley Field. Texas Rangers second baseman Julio Franco drives in both runs in the 7th inning and is named MVP.
- September 3 - Reliever Bobby Thigpen sets a major league record with his 47th save in a 4-2 Chicago White Sox victory over the Kansas City Royals. The previous record was set by Dave Righetti of the New York Yankees in 1986.
- September 22 - Andre Dawson of the Chicago Cubs steals his 300th base in an 11-5 loss to the New York Mets, becoming only the second player in major league history with 300 home runs, 300 steals and 2,000 hits; Willie Mays is the other.
- October 20 - The talk of an Oakland Athletics dynasty is proven premature, as the Cincinnati Reds beat Oakland 2–1 to complete one of the most stunning sweeps in World Series history. Series MVP José Rijo (2-0, 0.59 ERA) retires the last 20 batters he faces to give the Reds their first World Championship since 1976. Not joining the celebration at the end is Eric Davis, who ruptures his kidney diving for a ball during the game and is taken to the hospital. It will take Davis several years to fully recover.
- December 6 - At Leland's auction house in New York City, Shoeless Joe Jackson's signature is sold for $23,100, the most money ever paid for a 19th- or 20th-century signature. Jackson, who could not read or write, copied the signature from one written out by his wife. The signature, which is resold within hours, was cut from an unknown document.
- December 18 - The National League announces the six finalist cities for the two expansion clubs that will join the league in 1993: Buffalo, Denver, Miami, Orlando, Tampa-St. Petersburg and Washington, D.C.
- January 7 - Horace Stoneham, 86, owner of the Giants from 1936 to 1976 who moved the team from New York City to San Francisco for the 1958 season; the team won five NL pennants and the 1954 World Series during his tenure
- January 9 - Spud Chandler, 82, All-Star pitcher for the New York Yankees who was the AL's MVP in a 20-4 season in 1943; owned career .717 winning percentage
- February 24 - Tony Conigliaro, 45, All-Star right fielder for the Boston Red Sox who at age 20 became the younger player ever to win a home run title, but never fully recovered from being hit in the face by a pitch two years later
- March 6 - Joe Sewell, 91, Hall of Fame shortstop for the Cleveland Indians and New York Yankees who batted .312 lifetime and struck out only 114 times in over 8300 plate appearances; led AL in doubles in 1924, and in putouts and assists four times each
- March 26 - Chet Brewer, 83, All-Star pitcher of the Negro Leagues, later a scout for the Pirates
- March 29 - Phil Masi, 74, a four-time All-Star catcher who played for the Boston Braves, Pittsburgh Pirates and Chicago White Sox between 1939 and 1952
- May 23 - Charlie Keller, 73, 5-time All-Star left fielder for the New York Yankees who hit 30 home runs three times
- May 24 - Augie Donatelli, 75, National League umpire from 1950 to 1973 who initiated that league's trend toward a low strike zone, and spearheaded the formation of the first umpires' union
- July 28 - Red Barrett, 75, All-Star pitcher for three NL teams who set a major league record for the fewest pitches (58) in a nine-inning game in 1944; led NL in wins in 1945
- August 10 - Cookie Lavagetto, 77, All-Star third baseman who, with the Brooklyn Dodgers, spoiled a Yankee no-hitter with two out in the ninth inning of Game Four in the 1947 World Series, hitting a game-winning double; later managed the Senators and Twins
- August 28 - Larry Jackson, 59, All-Star pitcher who won 194 games for the Cardinals, Cubs and Phillies; led NL in wins in 1964
- September 9 - Doc Cramer, 85, 5-time All-Star center fielder for four AL teams who collected 2,705 hits and was a defensive standout; the only AL player to twice go 6-for-6 in a nine-inning game
- October 10 - Wally Moses, 80, All-Star right fielder for the Athletics, White Sox and Red Sox who hit .300 in his first seven seasons, led AL in doubles and triples once each
- November 8 - Earl Torgeson, 66, first baseman who hit .389 in 1948 World Series with Boston Braves, led NL in runs in 1950
- November 10 - Aurelio Monteagudo, 46, Cuban pitcher with five teams who also gained renown pitching in the Venezuelan and Mexican leagues
- November 23 - Baudilio "Bo" Díaz, 37, All-Star catcher, most notably with the Phillies and Reds, who batted .333 in the 1983 World Series