The Milwaukee Brewers' 1998 season was the first season for the franchise as a member of the National League. The Brewers finished in fifth in the National League Central, 28 games behind the Houston Astros, with a record of 74 wins and 88 losses. Before the 1998 regular season began, two new teams—the Arizona Diamondbacks and Tampa Bay Devil Rays—were added by Major League Baseball. This resulted in the American League and National League having 15 teams. However, in order for MLB officials to continue primarily intraleague play, both leagues would need to carry a number of teams that was divisible by two, so the decision was made to move one club from the AL Central to the NL Central. This realignment was widely considered to have great financial benefit to the club moving. However, to avoid the appearance of a conflict of interest, Commissioner (then club owner) Bud Selig decided another team should have the first chance to switch leagues. The choice was offered to the Kansas City Royals, who ultimately decided to stay in the American League. The choice then fell to the Brewers, who, on November 6, 1997, elected to move to the National League. Had the Brewers elected not to move to the National League, the Minnesota Twins would have been offered the opportunity to switch leagues. Fernando Vina became the first Brewer named as an National League All-Star.

Offseason

Regular season

Season standings

Record vs. opponents

Notable transactions

Roster

Player stats

Batting

Starters by position

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

Other batters

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

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; IP = Innings pitched; W = Wins; L = Losses; SV = Saves; ERA = Earned run average; SO = Strikeouts

Farm system

The Brewers' farm system consisted of eight minor league affiliates in 1998. The Brewers operated a Venezuelan Summer League team as a co-op with the Florida Marlins and San Francisco Giants. VSL Guacara 1 won the Venezuelan Summer League championship.