The 1977 Major League Baseball season saw the American League (AL) having its third expansion, as the Seattle Mariners and Toronto Blue Jays began play, with Seattle returning to the MLB fold after a seven-year absence when the Pilots relocated to Milwaukee to become the Brewers. However, the National League (NL) did not expand, remaining at 12 teams compared to the AL's 14, until the Colorado Rockies and Florida Marlins joined the NL in 1993. The season ended with the New York Yankees winning their 21st World Series title (and first since 1962) over the Los Angeles Dodgers.

Standings

American League

National League

Postseason

Bracket

<section begin=Bracket/> <section end=Bracket/>

Awards and honors

Major Awards

Gold Glove Awards

Statistical leaders

All-Star game

Feats

No-Hitters

Cycles

Career milestones

400 home runs

900 stolen bases

Home field attendance

Notable events

January–March

April–June

July–September

October–December

Television coverage

ABC aired Monday Night Baseball and the World Series. NBC televised the weekend Game of the Week, the All-Star Game, and both League Championship Series.