1999 New York Mets season

The 1999 New York Mets season was the franchise's 38th season and the team's 36th season at Shea Stadium. They went 97–66 and finished second in the National League East but won the NL Wild Card by beating the Cincinnati Reds in a one-game playoff. The Mets advanced to the NLCS, where they were defeated by the Atlanta Braves in 6 games.

The Mets were managed by Bobby Valentine, who entered his fourth year as skipper. They played home games at Shea Stadium.

Offseason

 * November 11, 1998: Bobby Bonilla was traded by the Los Angeles Dodgers to the New York Mets for Mel Rojas.
 * December 1, 1998: Todd Hundley was traded by the New York Mets with Arnold Gooch (minors) to the Los Angeles Dodgers for Roger Cedeño and Charles Johnson.
 * December 1, 1998: Charles Johnson was traded by the New York Mets to the Baltimore Orioles for Armando Benítez.
 * December 1, 1998: Robin Ventura was signed as a free agent with the New York Mets.
 * December 16, 1998: Rickey Henderson signed as a free agent with the New York Mets.
 * December 18, 1998: Josías Manzanillo was signed as a free agent with the New York Mets.

Regular season
The Mets' 97 victories were their highest total since they won 100 games in 1988. They were led offensively by catcher Mike Piazza, who compiled a .303 average with 40 home runs and 124 RBI in his first full season with the team. New third baseman Robin Ventura put together a .301 average, 32 home runs, and 120 RBI while second baseman Edgardo Alfonzo hit .304 with 27 home runs and 108 RBI. First baseman John Olerud continued his consistent hitting, hitting .298 with 96 RBI, his third straight year with 90 or more runs driven in. Offseason acquisitions Roger Cedeño and Rickey Henderson recorded the two highest batting averages on the squad at .315 and .313 respectively. Benny Agbayani, a semi-regular outfielder who got more playing time as the year progressed, contributed 14 home runs.

The Mets' pitching staff was again led by Al Leiter with 13 wins. Orel Hershiser matched that total, with Masato Yoshii recording 12 wins and Rick Reed 11. Rookie Octavio Dotel went 8-3 in fourteen starts, and late season acquisition Kenny Rogers won five of six decisions while leading the team in complete games. The rotation was not as strong at keeping runs off the board; the team's four main starters recorded ERAs above 4.00.

The offseason acquisition of Armando Benitez from the Baltimore Orioles ended John Franco's tenure as the team's closer. Franco did manage to record nineteen saves and broke the Major League Baseball record for saves by a left-hander, but Benitez' 1.85 ERA and twenty-two saves ensured the closer role would be his for the foreseeable future.

Mercury Mets
As part of the now-infamous Turn Ahead the Clock promotion sponsored by Century 21, the Mets changed their name to the "Mercury Mets" while hosting the Pittsburgh Pirates on July 27, 1999.

Opening Day starters

 * SP – Al Leiter
 * C – Mike Piazza
 * 1B – John Olerud
 * 2B – Edgardo Alfonzo
 * 3B – Robin Ventura
 * SS – Rey Ordóñez
 * LF – Rickey Henderson
 * CF – Brian McRae
 * RF – Bobby Bonilla

Notable transactions

 * July 31, 1999: Brian McRae was traded by the New York Mets with Thomas Johnson (minors) and Rigo Beltrán to the Colorado Rockies for Darryl Hamilton and Chuck McElroy.
 * July 31, 1999: Jason Isringhausen was traded by the New York Mets with Greg McMichael to the Oakland Athletics for Billy Taylor.

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''

Starting pitchers
Note: G = Games pitched; GS = Games started; 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
LEAGUE CHAMPIONS: GCL Mets