American League

• Milwaukee Brewers – AL East champions, 95–67^[2]
• California Angels – AL West champions, 93–69^[3]

National League

• St. Louis Cardinals – NL East champions, 92–70^[4]
• Atlanta Braves – NL West champions, 89–73^[5]

Milwaukee Brewers vs. California Angels

Milwaukee won the series, 3–2.

This was the first playoff matchup between two expansion teams. Down two games to none, the Brewers managed to rally and defeat the Angels in 5 games en route to their first World Series in franchise history.

In Anaheim, the Angels blew out the Brewers in Game 1 as Tommy John pitched a complete game, and then won Game 2 by a 4-2 score to go up two games to none headed to Milwaukee. The Brewers narrowly took Game 3 as closer Pete Ladd held off a late rally by the Angels. Game 4 was an offensive duel which was won by the Brewers, 9-5, as they evened the series. In Game 5, the Brewers overcame a late Angels lead to win as Cecil Cooper drove in two runs with an RBI single, clinching the pennant. The Brewers became the first team in LCS history to come back from a two games to none deficit to win the pennant. This would be the last playoff series win by the Brewers until 2011.

The Angels returned to the postseason in 1986, but they would lose to the Boston Red Sox in the ALCS. It would be in 2002 that the Angels would finally win the pennant, as well as the World Series.

As of 2023, this is the only time the Brewers won a pennant.

Atlanta Braves vs. St. Louis Cardinals

St. Louis won the series, 3–0.

This was the first postseason meeting between the Cardinals and Braves. It was also the first NLCS since 1969 to not feature a team from Ohio, Pennsylvania, or California. The Cardinals swept the Braves and returned to the World Series for the first time since 1968.

This series was heavily lopsided in favor of the Cardinals - Bob Forsch pitched a complete-game shutout as the Cardinals blew out the Braves, 7-0, in Game 1. The Braves held a 3-2 lead after seven innings, but the Cardinals rallied with one run scored in the bottom of the eighth and ninth innings respectively to take a 2-0 series lead headed to Atlanta. In Game 3, the Cardinals jumped out to a big lead early and maintained it, as Joaquín Andújar and closer Bruce Sutter held the Braves' offense at bay to help the Cardinals win 6-2 and clinch the pennant.

The Braves would not return to the postseason until 1991, where they went on a long postseason appearance streak which ended in 2005. The Braves and Cardinals would meet again in the NLCS in 1996, where the Braves defeated the Cardinals in seven games to capture their second straight NL pennant after trailing three games to one.

This was the first of three NL pennants won by the Cardinals during the 1980s, as they would win it again in 1985 against the Los Angeles Dodgers, and in 1987 against the San Francisco Giants.

Milwaukee Brewers (AL) vs. St. Louis Cardinals (NL)

St. Louis won the series, 4-3.

This was the first World Series since 1968 to not feature a team from New York, Pennsylvania, Maryland, Ohio, or California.

This was the first time the World Series was played in the state of Wisconsin since 1958, when the then-Milwaukee Braves, the defending World Series champions, were defeated by the New York Yankees in seven games. It was also the first postseason meeting between the Brewers and Cardinals. The Brewers took a 3-2 series lead going back to St. Louis, but the Cardinals took Game 6 and came back late in Game 7 to win their first title since 1967. This marked the fourth consecutive World Series win by the National League.

In St. Louis, the Brewers blew out the Cardinals, 10-0, to take Game 1 as Mike Caldwell pitched a three-hit complete-game shutout. The Cardinals narrowly won Game 2 to even the series going to Milwaukee. The Cardinals won Game 3 by a 6-2 score to take a 2-1 series lead and regain the home field advantage. Then, the Brewers won Games 4 and 5 by two runs to be one win away from their first ever World Series title. When the series moved back to St. Louis, the Cardinals routed the Brewers by a 13-1 score to force a Game 7, with John Stuper pitching a complete game for the Cardinals. In Game 7, the Brewers led 3-1 going into the bottom of the sixth, until Brewers' manager Harvey Kuenn pulled starting pitcher Pete Vuckovich after the Cardinals got men on first and third bases with one out. This decision proved to be fatal for the Brewers, as the Cardinals scored three runs to take the lead, and then scored two more unanswered runs in the bottom of the eighth to secure the title.

This would be the final postseason appearance by the Brewers as a member of the American League. They would return to the postseason in 2008 as a member of the National League. The Cardinals would make two more World Series appearances during the decade, in 1985 and 1987, losing both to the Kansas City Royals and Minnesota Twins respectively. The Brewers and Cardinals would meet again in the 2011 NLCS, which the Cardinals also won. The Cardinals would not win the World Series again until 2006, where they defeated the Detroit Tigers in five games.