During the 1966 Houston Astros season in American baseball, the team finished eighth in the National League with a record of .440, 23 games behind the Los Angeles Dodgers. This was the second season for the Astrodome, but its first with a playing surface of AstroTurf. The infield portion was installed in March, and the outfield was ready for play on July 19.

Offseason

Regular season

Season standings

Record vs. opponents

Opening Day lineup

Notable transactions

Roster

Player stats

Batting

Starters by position

''Note: Pos = Position; G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Other batters

''Note: G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Pitching

Starting pitchers

Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Other pitchers

Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Relief pitchers

Note: G = Games pitched; W = Wins; L = Losses; SV = Saves; ERA = Earned run average; SO = Strikeouts

Farm system