The 2003 Stanley Cup playoffs, the playoff tournament of the National Hockey League (NHL), began on April 9, 2003, following the 2002–03 regular season. The playoffs concluded on June 9, 2003, with the New Jersey Devils defeating the Mighty Ducks of Anaheim in seven games.

The 16 qualifying teams played best-of-seven series in the conference quarterfinals, semifinals, and finals. Each conference champion proceeded to the Stanley Cup Finals. These playoffs marked the first time the Minnesota Wild qualified, in only their third season in the NHL. The Minnesota Wild, a sixth-seed, made an unlikely advance to the Western Conference Final as underdogs after being down three games to one in two consecutive rounds. This, along with the Canucks' comeback against the Blues, made for three 3–1 series comebacks in the playoffs, the second time this had happened in NHL playoff history, after 1992.

Despite losing to the Devils in the Stanley Cup Finals, Mighty Ducks goaltender Jean-Sebastien Giguere was awarded the Conn Smythe Trophy as the Most Valuable Player during the playoffs, marking only the fifth time that the Trophy had ever been awarded to a player on the losing team.

Playoff seeds The top eight teams in each conference qualified for the playoffs. The top three seeds in each conference were awarded to the division winners; while the five remaining spots were awarded to the highest finishers in their respective conferences.

The following teams qualified for the playoffs:

Eastern Conference Ottawa Senators, Northeast Division champions, Eastern Conference regular season champions, Presidents' Trophy winners – 113 points New Jersey Devils, Atlantic Division champions – 108 points Tampa Bay Lightning, Southeast Division champions – 93 points Philadelphia Flyers – 107 points Toronto Maple Leafs – 98 points Washington Capitals – 92 points Boston Bruins – 87 points New York Islanders – 83 points

Western Conference Dallas Stars, Pacific Division champions, Western Conference regular season champions – 111 points Detroit Red Wings, Central Division champions – 110 points Colorado Avalanche, Northwest Division champions – 105 points Vancouver Canucks – 104 points St. Louis Blues – 99 points Minnesota Wild – 95 points (42 wins) Mighty Ducks of Anaheim – 95 points (40 wins) Edmonton Oilers – 92 points

Playoff bracket In each round, teams competed in a best-of-seven series following a 2–2–1–1–1 format (scores in the bracket indicate the number of games won in each best-of-seven series). The team with home ice advantage played at home for games one and two (and games five and seven, if necessary), and the other team played at home for games three and four (and game six, if necessary). The top eight teams in each conference made the playoffs, with the three division winners seeded 1–3 based on regular season record, and the five remaining teams seeded 4–8.

The NHL used "re-seeding" instead of a fixed bracket playoff system. During the first three rounds, the highest remaining seed in each conference was matched against the lowest remaining seed, the second-highest remaining seed played the second-lowest remaining seed, and so forth. The higher-seeded team was awarded home ice advantage. The two conference winners then advanced to the Stanley Cup Finals, where home ice advantage was awarded to the team that had the better regular season record.

Conference quarterfinals

Eastern Conference quarterfinals

(1) Ottawa Senators vs. (8) New York Islanders The Ottawa Senators finished as the first overall seed in the Eastern Conference with 113 points. The New York Islanders earned 83 points during the regular season to finish eighth overall in the Eastern Conference. This was the first playoff series between these two teams. Ottawa won the four game regular season series by earning five of eight points in their matchup.

The Senators defeated the Islanders in five games. In game one, Roman Hamrlik assisted on two of the three goals and Islanders goalie Garth Snow shut out the Senators stopping all 25 shots he faced in a 3–0 victory. The Senators responded in game two by shutting out the Islanders 3–0; goalie Patrick Lalime stopped all 16 shots he faced. Overtime was required in game three with both teams tied at two at the end of the third period. At 2:25 of the second overtime, Todd White scored his second goal of the game to give the Senators a 3–2 victory. In game four, Marian Hossa had a goal and an assist to help the Senators take a 3–1 series lead in a 3–1 win. In game five, Todd White's goal at 11:05 of the second period proved to be the game-winner and series-winner for the Senators with Radek Bonk providing two insurance goals in a 4–1 victory.

(2) New Jersey Devils vs. (7) Boston Bruins The New Jersey Devils entered the playoffs as the second seed in the Eastern Conference and won the Atlantic Division title with 108 points. The Boston Bruins finished seventh overall in the Eastern Conference with 87 points. This was the fourth playoff meeting between these two teams with New Jersey winning two of three previous series. They last met in the 1995 Eastern Conference Quarterfinals which New Jersey won in five games. New Jersey won this year's four game regular season series earning five of eight points.

The Devils defeated the Bruins in five games. In game one, Jamie Langenbrunner scored both New Jersey goals before Boston came within one goal in the third period. New Jersey hung on for a 2–1 win. Jamie Langenbrunner had a goal and two assists in game two to help the Devils achieve a 4–2 victory and a 2–0 series lead. In game three, goalie Martin Brodeur shut out the Bruins, stopping all 29 shots in a 3–0 victory. The Boston Bruins forced a fifth game on two goals by Dan McGillis as well as two assists provided by Mike Knuble and Brian Rolston in a 5–1 win. The Devils closed out the series in game five with Jamie Langenbrunner scoring twice and Martin Brodeur stopping all 28 shots he faced in a 3–0 win.

(3) Tampa Bay Lightning vs. (6) Washington Capitals The Tampa Bay Lightning entered the playoffs for only the second time in their history as the third seed in the Eastern Conference and won the Southeast Division title with 93 points. The Washington Capitals finished sixth overall in the Eastern Conference with 92 points. This was the first playoff meeting between these two teams. Washington won three of the five games in this year's regular season series.

The Lightning came back from 2–0 down to defeat the Capitals in six games. Robert Lang provided two goals and Olaf Kolzig stopped all 28 shots to give the Capitals a 3–0 victory in game one. Game two saw Jaromir Jagr score two goals and two assists in a 6–3 win for Washington. The Lightning scored three times in game three; each time though Washington tied the score. Finally in overtime, Vincent Lecavalier scored a power-play goal to give Tampa Bay a 4–3 victory. With a chance to tie the series in game four, Martin St. Louis scored twice to help the Lightning earn a 3–1 victory. In game five, St. Louis contributed a goal and an assist, including the game-winning goal with 8:07 left in the third period, to aid the Lightning in a 2–1 win and took a 3–2 series lead. The Capitals tried to avoid elimination in game six by sending the game into overtime, however, St. Louis' power-play goal at 4:03 of the third overtime ended Washington's season despite putting up 61 shots against goalie Nikolai Khabibulin. The Lightning won the game 2–1 and won their first playoff series in franchise history.

(4) Philadelphia Flyers vs. (5) Toronto Maple Leafs The Philadelphia Flyers finished as the fourth seed in the Eastern Conference with 107 points. The Toronto Maple Leafs finished as the fifth seed in the Eastern Conference with 98 points. This was the fifth playoff meeting between these two teams with Philadelphia winning three of the previous four series. They last met in the 1999 Eastern Conference Quarterfinal, which Toronto won in six games. The teams split this year's four game regular season series.

The Flyers defeated the Maple Leafs in seven games. In game one, Alexander Mogilny scored a hat trick to give Toronto a 5–3 victory. The Flyers responded to the loss with a 4–1 win in game two with John LeClair, Mark Recchi, and Simon Gagne all contributing a goal and an assist. In game three, Toronto came back from an early two-goal deficit to win the game in double overtime on a goal by Tomas Kaberle, his second of the game. Game four showcased a triple overtime game in which Philadelphia nearly doubled the shots Toronto took. On the 75th shot for the Flyers, at 13:54 of the third overtime Mark Recchi scored his second goal of the game to help the Flyers take a 3–2 win. Sami Kapanen scored two power play goals in game five to assist the Flyers in a 4–1 win and took a 3–2 series lead. In game six, Robert Reichel opened the scoring after a distracted Roman Cechmanek was attempting to put his glove back on as he had lost it behind the net. Toronto forced a seventh game with 35 saves from Ed Belfour and a game-winning goal from Travis Green in double overtime. The Flyers routed the Maple Leafs in game seven 6–1 with Mark Recchi scoring two goals and an assist and Justin Williams and Claude Lapointe both scoring a goal and two assists.

Western Conference quarterfinals

(1) Dallas Stars vs. (8) Edmonton Oilers The Dallas Stars finished first in the Western Conference with 111 points. The Edmonton Oilers finished as the eighth seed in the Western Conference with 92 points. This was the sixth playoff meeting within the last seven years and the eighth overall between these two teams; Dallas won five of the previous seven playoff series. They last met in the 2001 Western Conference Quarterfinals which Dallas won in six games. Dallas won three of the four games in this year's regular season series.

In game one, Edmonton scored two goals in the second period 3:48 apart to take the lead and then win the game 2–1. Dallas controlled game two by allowing only 13 shots on goal, and five different players scored in a 6–1 victory including Scott Young who had two goals and an assist. In game three, Edmonton scored three times within 3:05 to take a 3–2 lead early in the third period to win the game. Eric Brewer assisted on two of the goals. The Stars evened the series in game four by scoring 23 seconds apart in the third period taking a 3–1 victory as a result. In game five, Sergei Zubov scored two goals in a 5–2 win for the Stars. Although Edmonton tied the game in the second period after being down two goals, Mike Modano's goal at 13:08 of the third period proved to be the series-winner.

(2) Detroit Red Wings vs. (7) Mighty Ducks of Anaheim The Detroit Red Wings finished as the second seed in the Western Conference, winning the Central Division with 110 points. The Mighty Ducks of Anaheim finished as the seventh seed with 95 points (losing the tiebreaker with Minnesota in total wins). This was the third playoff meeting between these two teams with Detroit winning both previous series via four-game sweeps. They last met in the 1999 Western Conference Quarterfinals which Detroit won in four games. Detroit won three of the four games in this year's regular season series.