1991 in sports

• Alpine Skiing World Cup
  • Men's overall season champion: Marc Girardelli, Luxembourg
  • Women's overall season champion: Petra Kronberger, Austria

• Super Bowl XXV – New York Giants won 20–19 over the Buffalo Bills
• Thurman Thomas of the Buffalo Bills is named the NFL MVP
• Orange Bowl (1990 season):
  • The Colorado Buffaloes won 10-9 over the Notre Dame Fighting Irish to win the AP Poll national championship
• Desmond Howard, University of Michigan wide receiver seals the Heisman Trophy with a 93-yard punt return in Michigan's 31–3 hammering of Ohio State.
• World Bowl ‘91: London Monarchs won 21–0 over the Barcelona Dragons in the inaugural World Bowl.
• Quarterback Stan Gelbaugh of the London Monarchs is named the World League of American Football's inaugural seasons Most Valuable Player

• World Artistic Gymnastics Championships –
  • Men's all-around champion: Grigory Misutin, USSR
  • Women's all-around champion: Kim Zmeskal, United States
  • Men's team competition champion: USSR
  • Women's team competition champion: USSR

• European Cup – FK Red Star beat Olympique de Marseille 5–3 on penalties (0–0 aet)
• FIFA Women's World Cup – United States won 2–1 over Norway

• 1991 World Championships in Athletics held in Tokyo
• 30 August – Track & Field World Championship Mike Powell breaking Bob Beamon's 23-year-old Long Jump world record with a mark of 29' 4 1/2"

• Australian Football League
  • The Adelaide Crows join the league
  • 25 April – North Melbourne and Sydney kick between them 32.18 (210) in the first half. It is the record aggregate score for a half of VFL/AFL football.
  • 2 June – Carlton kick their first goal with 33 second to go against Footscray, the closest a team has come to finishing goalless since Richmond kicked 0.8 (8) in 1961 against St. Kilda.
  • 8 September – Hawthorn beat West Coast 18.16 (124) to 15.11 (101) in the first final outside Melbourne.
  • 1991 AFL Grand Final (28 September) – Hawthorn wins the 95th AFL premiership beating West Coast 20.19 (139) to 13.8 (86) in the only Grand Final at VFL Park.
  • Brownlow Medal awarded to Jim Stynes (Melbourne)
• 7 October – death of Darren Millane, who played for Collingwood between 1984 and 1991, from a car crash in Prahran.

• Dave Righetti breaks Sparky Lyle's major league record for left-handers of 238 career saves.
• 1 May – Nolan Ryan pitchers his seventh career no hitter with a 3–0 victory over the Toronto Blue Jays
• 28 July – Dennis Martínez of the Montreal Expos pitches the 13th perfect game in major league history, beating the Los Angeles Dodgers 2–0.
• World Series – The Minnesota Twins win 4 games to 3 over the Atlanta Braves. The series MVP is Jack Morris of Minnesota.
• Cal Ripken, Jr. of the Baltimore Orioles is named AL MVP
• Terry Pendleton of the Atlanta Braves is named NL MVP
• Roger Clemens of the Boston Red Sox is named AL Cy Young award winner. It is his third of six in his career
• Tom Glavine of the Atlanta Braves is named NL Cy Young award winner
• Chuck Knoblauch of the Minnesota Twins is named AL Rookie of the Year
• Jeff Bagwell of the Houston Astros is named NL Rookie of the Year

• NCAA Men's Basketball Championship – Duke wins 72–65 over Kansas
• Larry Johnson of UNLV is named Naismith College Player of the Year
• 9 February – Dee Brown win the Gatorade Slam Dunk Contest
• 10 February – NBA All-Star Game is held in Charlotte, North Carolina
• 12 June – NBA Finals: Chicago Bulls win 4 games to 1 over the Los Angeles Lakers to earn the franchise's first championship, starting a run of six titles in eight seasons.
• Michael Jordan is named the NBA MVP, his second of 5 awards.
• 7 November – Lakers’ superstar Magic Johnson announces he tested positive for the virus that causes AIDS, thus ending his career in the NBA.
• National Basketball League (Australia) Finals: Perth Wildcats defeated the Eastside Melbourne Spectres 2–1 in the best-of-three final series.
• 17 December – The Cleveland Cavaliers beat the Miami Heat 148 to 80, the largest margin of victory in any NBA game.

• 3 March – Mike Tyson defeats Donovan Ruddock in a seventh-round TKO
• 19 April – Evander Holyfield defeats George Foreman to retain WBC, WBA & IBF Heavyweight titles
• 7 to 12 May – 29th European Amateur Boxing Championships held in Gothenburg, Sweden
• 3 June – Thomas Hearns defeats Virgil Hill with a unanimous decision to win WBA Light Heavyweight title
• 1 June at Palm Springs, California – Terry Norris knocked out Donald Curry in the 8th Round to win the WBC Super Welterweight Championship.
• 28 June Mike Tyson defeats Donovan Ruddock in a rematch with a 12-round unanimous decision
• 2 to 18 August – Pan American Games held in Havana, Cuba.
• 5 October – James Toney defeats Michael Nunn with a TKO to win IBF Middleweight title
• James Toney is named Ring Magazine fighter of the year

• Grey Cup – Toronto Argonauts win 36–21 over the Calgary Stampeders
• B.C. Lions Quarterback Doug Flutie is named CFL Most Outstanding Player
• Vanier Cup – Wilfrid Laurier Golden Hawks win 25–18 over the Mount Allison Mounties

• South Africa readmitted to the International Cricket Council following the abolition of apartheid, and play their first international game since 1970.

• Giro d'Italia won by Franco Chiocciolo of Italy
• Tour de France – Miguel Indurain of Spain
• UCI Road World Championships – Men's road race – Gianni Bugno of Italy

• Iditarod Trail Sled Dog Race Champion –
  • Rick Swenson won with lead dog: Goose

• Men's Champions Trophy: Germany
• Women's Champions Trophy: Australia

• World Figure Skating Championships –
  • Men's champion: Kurt Browning, Canada
  • Ladies’ champion: Kristi Yamaguchi, United States
  • Pair skating champions: Natalia Mishkutenok & Artur Dmitriev, Soviet Union
  • Ice dancing champions: Isabelle Duchesnay & Paul Duchesnay, France

Men's professional

• Masters Tournament – Ian Woosnam
• U.S. Open – Payne Stewart
• British Open – Ian Baker-Finch
• PGA Championship – John Daly
• PGA Tour money leader – Corey Pavin – $979,430
• Senior PGA Tour money leader – Mike Hill – $1,065,657
• Ryder Cup – United States team won 14½ – 13½ over the Europe in team golf.

Men's amateur

• British Amateur – Gary Wolstenholme
• U.S. Amateur – Mitch Voges
• European Amateur – Jim Payne
• Tiger Woods, at age 15, won his first USGA title, the U.S. Junior Amateur.

Women's professional

• Nabisco Dinah Shore – Amy Alcott
• LPGA Championship – Meg Mallon
• U.S. Women's Open – Meg Mallon
• Classique du Maurier – Nancy Scranton
• LPGA Tour money leader – Pat Bradley – $763,118

• North America Cup – Precious Bunny
• United States Pacing Triple Crown races –
  1. Cane Pace – Silky Stallone
  2. Little Brown Jug – Precious Bunny
  3. Messenger Stakes – Die Laughing
• United States Trotting Triple Crown races –
  1. Hambletonian – Giant Victory
  2. Yonkers Trot –
  3. Kentucky Futurity – Whiteland Janice
• Australian Inter Dominion Harness Racing Championship –
  • Pacers: Mark Ranover
  • Trotters: Fraggle Rock

Steeplechases

• Cheltenham Gold Cup – Garrison Savannah
• Grand National – Seagram

Flat races

• Australia – Melbourne Cup won by Let's Elope
• Canadian Triple Crown Races:
  1. Queen's Plate – Dance Smartly
  2. Prince of Wales Stakes – Dance Smartly
  3. Breeders' Stakes – Dance Smartly
  • Dance Smartly becomes the country's third consecutive Triple Crown winner.
• France – Prix de l'Arc de Triomphe won by Suave Dancer
• Ireland – Irish Derby Stakes won by Generous
• Japan – Japan Cup won by Golden Pheasant
• English Triple Crown Races:
  1. 2,000 Guineas Stakes – Mystiko
  2. The Derby – Generous
  3. St. Leger Stakes – Toulon
• United States Triple Crown Races:
  1. Kentucky Derby – Strike the Gold
  2. Preakness Stakes – Hansel
  3. Belmont Stakes – Hansel
• Breeders' Cup World Thoroughbred Championships:
  1. Breeders' Cup Classic – Black Tie Affair
  2. Breeders' Cup Distaff – Dance Smartly
  3. Breeders' Cup Juvenile – Arazi
  4. Breeders' Cup Juvenile Fillies – Pleasant Stage
  5. Breeders' Cup Mile – Opening Verse
  6. Breeders' Cup Sprint – Sheikh Albadou
  7. Breeders' Cup Turf – Miss Alleged

• Art Ross Trophy as the NHL's leading scorer during the regular season: Wayne Gretzky, Los Angeles Kings
• Hart Memorial Trophy for the NHL's Most Valuable Player: Brett Hull, St. Louis Blues
• Stanley Cup
  • Pittsburgh Penguins win 4 games to 2 over the Minnesota North Stars
• Conn Smythe Trophy – Mario Lemieux, Pittsburgh Penguins
• World Hockey Championship
  • Men's champion: Sweden defeated Canada
  • Junior Men's champion: Canada defeated the USSR
• Sheffield Steelers formed
• San Jose Sharks formed
• Northern Michigan University wins the NCAA Division I title in hockey, 8–7 in the third overtime against Boston University.

• The Detroit Turbos defeat the Baltimore Thunder to win the Major Indoor Lacrosse League championship

• The Friendship Radiosport Games held in Portland, Oregon, United States was the first international Amateur Radio Direction Finding competition held in the Americas.
• Third European High Speed Telegraphy Championship held in Neerpelt, Belgium.

• Penrith Panthers defeat two-time defending premiers Canberra Raiders in the NSWRL Grand Final at the Sydney Football Stadium. It is Penrith's first premiership since their admission in 1967.
• Wigan retained their title in the English Rugby League competition, with Oldham, Sheffield Eagles and Rochdale Hornets being relegated. To date this is Rochdale's last appearance in the top flight.

• 97th Five Nations Championship series is won by England who complete the Grand Slam
• Australia wins the 1991 Rugby World Cup

• World Snooker Championship – John Parrott beats Jimmy White 18–11
• World rankings – Stephen Hendry remains world number one for 1991/92

• The sixth FINA World Championships, held in Perth, Australia (3 January – 13)
• Eleventh Pan American Games held in Havana, Cuba (12–18 August)
• 20th European LC Championships, held in Athens, Greece (18–25 August)
• Fourth Pan Pacific Championships, held in Edmonton, Alberta, Canada (22–25 August)
• First European Sprint Championships, held in Gelsenkirchen, Germany (6–8 December)
• 13 December – Steve Crocker sets the first official world record in the men's 50m freestyle (short course) in Sheffield, United Kingdom, clocking 25.64.

• World Championships held in Athens, Greece

• 20 June – death of Michael Westphal (26), German player
• Grand Slam in tennis men's results:
  1. Australian Open – Boris Becker
  2. French Open – Jim Courier
  3. Wimbledon championships – Michael Stich
  4. US Open – Stefan Edberg
• Grand Slam in tennis women's results:
  1. Australian Open – Monica Seles
  2. French Open – Monica Seles
  3. Wimbledon championships – Steffi Graf
  4. US Open – Monica Seles
• Davis Cup – France won 3–1 over the United States in world tennis.

• ITU World Championships held in Gold Coast, Australia
• ITU World Cup (eleven races) started in the United States Virgin Islands and ended in Mexico
• ETU European Championships held in Geneva, Switzerland

Men's competition

• FIVB World League: Italy
• Asia Volleyball Championship: Japan
• Men's European Volleyball Championship: USSR
• Pan American Games: Cuba

Women's competition

• Asia Volleyball Championship: China
• Women's European Volleyball Championship: USSR
• Pan American Games: Cuba

• FINA Men's World Water Polo Championship: Yugoslavia
• FINA Women's World Water Polo Championship: Netherlands

• Eleventh Pan American Games held in Havana, Cuba
• Fifth All-Africa Games held in Cairo, Egypt
• Eleventh Mediterranean Games held in Athens, Greece
• Sixteenth Summer Universiade held in Sheffield, United Kingdom
• Fifteenth Winter Universiade held in Sapporo, Japan
• Sixteenth Southeast Asian Games held in Manila, Philippines

• Associated Press Male Athlete of the Year – Michael Jordan, NBA basketball
• Associated Press Female Athlete of the Year – Monica Seles, Tennis
• Sports Illustrated Sportsman of the Year – Michael Jordan
• James E. Sullivan Award – Olympic Long Jumper Mike Powell