1948 in sports describes the year's events in world sport.

• NFL Championship: the Philadelphia Eagles won 7–0 over the Chicago Cardinals at Shibe Park in a blizzard
• Michigan Wolverines – college football national championship
• Cleveland Browns defeated the Buffalo Bills 49–7 in the All-America Football Conference championship game.

Egypt

• Egyptian Premier League founded.^[1]

England

• First Division – Arsenal win the 1947–48 title.
• FA Cup – Manchester United beat Blackpool 4–2.

33 athletics events were contested at the Olympic Games in London, including debuts for the men's 10 km walk; and the women's 200 metres, long jump and shot put. Fanny Blankers-Koen of the Netherlands captured four gold medals.

Victorian Football League

• Melbourne wins the 52nd VFL Premiership, drawing the 1948 VFL Grand Final with Essendon 10.9 (69) to 7.27 (69), and winning the replay 13.11 (89) to Essendon's 7.8 (50)
• Brownlow Medal awarded to Bill Morris (Richmond)

South Australian National Football League

• 2 October – Norwood wins its twenty-first SANFL premiership, defeating West Torrens 15.16 (106) to 7.7 (49)
• Magarey Medal awarded to Ron Phillips (North Adelaide)

Western Australian National Football League

• 9 October – South Fremantle wins its fourth premiership and second in succession, defeating West Perth 13.9 (87) to 9.9 (63)
• Sandover Medal awarded to Merv McIntosh (Perth)

• January 29 – Commissioner Happy Chandler fines the Yankees, Cubs, and Phillies $500 each for signing high school players.
• February 27 – Hall of Fame election – voters select the recently deceased Herb Pennock, and Pie Traynor, as the newest inductees; Traynor is the first third baseman elected by the writers in 9 elections.
• August 16 – death of Babe Ruth
• World Series – Cleveland Indians defeat Boston Braves, 4 games to 2.
• Negro World Series – Homestead Grays defeat the Birmingham Black Barons, 4 games to 1.
• College World Series - University of Southern California defeat Yale in the 2nd 2 games to 1

NCAA Basketball Championship

• Kentucky beat Baylor 58–42^[2]

BAA (NBA) Finals

• Baltimore Bullets over the Philadelphia Warriors (4–2)

NBL Championship

• Minneapolis Lakers over Rochester Royals (3–1)

• June 25 – At New York's Yankee Stadium – Joe Louis knocked out Jersey Joe Walcott in the 11th round to retain his heavyweight title for the 25th time. Shortly after the bout, Louis announced his retirement from boxing.

• Olympic Games (men's competition) in London, Great Britain^[3]
  • Gold: India
  • Silver: Great Britain
  • Bronze: Netherlands

• World Figure Skating Championships
  • Men's champion: Dick Button, United States^[4]
  • Ladies' champion: Barbara Ann Scott, Canada
  • Pair skating champions: Micheline Lannoy & Pierre Baugniet, Belgium

Men's professional

• Masters Tournament – Claude Harmon
• PGA Championship – Ben Hogan
• U.S. Open – Ben Hogan
• British Open – Henry Cotton

Men's amateur

• British Amateur – Frank Stranahan
• U.S. Amateur – Willie Turnesa

Women's professional

• Women's Western Open – Patty Berg
• U.S. Women's Open – Babe Zaharias
• Titleholders Championship – Patty Berg

• NCAA Men's Ice Hockey Championship – Michigan Wolverines defeat Dartmouth College Big Green 8–4 in Colorado Springs, Colorado to win the first official NCAA championship
• Stanley Cup – Toronto Maple Leafs beat Detroit Red Wings in 4 straight games to win their 5th Stanley Cup title.

• Citation becomes the 8th horse to win the US Triple Crown
• Shiela's Cottage becomes the first mare to win the Grand National since 1902 and only the twelfth since the race's inception

Steeplechases

• Cheltenham Gold Cup – Cottage Rake
• Grand National – Sheila's Cottage

Hurdle races

• Champion Hurdle – National Spirit

Flat races

• Australia – Melbourne Cup won by Rimfire (horse)
• Canada – King's Plate won by Last Mark
• France – Prix de l'Arc de Triomphe won by Migoli
• Ireland – Irish Derby Stakes won by Nathoo
• English Triple Crown Races:
  1. 2,000 Guineas Stakes – My Babu
  2. The Derby – My Love^[5]
  3. St. Leger Stakes – Black Tarquin
• United States Triple Crown Races:
  1. Kentucky Derby – Citation
  2. Preakness Stakes – Citation
  3. Belmont Stakes – Citation

• 1948 Summer Olympics takes place in London, United Kingdom
  • United States wins the most medals (84) and the most gold medals (38).^[6]
• 1948 Winter Olympics takes place in St. Moritz, Switzerland
  • Norway, Sweden and Switzerland all win the most medals (10 each), and Norway and Sweden win the most gold medals (4 each).^[7]

• First CQ World Wide DX Contest held in October and November. This annual event would go on to become the radio contest with the largest participation worldwide.

The Boat Race

• 27 March — Cambridge wins the 94th Oxford and Cambridge Boat Race

Australia

• 1948 NSWRFL season

England

• 1947–48 Northern Rugby Football League season/1948–49 Northern Rugby Football League season

Five Nations Championship

• 54th Five Nations Championship series is won by Ireland who complete the Grand Slam, their last for 61 years.

• World Snooker Championship – Fred Davis beats Walter Donaldson 84–61.

Speed Skating World Championships

• Men's All-round Champion – Odd Lundberg (Norway)
• Women's All-round Champion – Maria Isakova (USSR)

1948 Winter Olympics (Men)

• 500m – gold medal: Finn Helgesen (Norway)
• 1500m – gold medal: Sverre Farstad (Norway)
• 5000m – gold medal: Reidar Liaklev (Norway)
• 10000m – gold medal: Åke Seyffarth (Sweden)

1948 Winter Olympics (Women)

• not contested

Australia

• Australian Men's Singles Championship – Adrian Quist (Australia) defeats John Bromwich (Australia) 6–4, 3–6, 6–3, 2–6, 6–3
• Australian Women's Singles Championship – Nancye Wynne Bolton (Australia) defeats Marie Toomey (Australia) 6–3, 6–1

England

• Wimbledon Men's Singles Championship – Bob Falkenburg (USA) defeats John Bromwich (Australia) 7–5, 0–6, 6–2, 3–6, 7–5
• Wimbledon Women's Singles Championship – Louise Brough Clapp (USA) defeats Doris Hart (USA) 6–3, 8–6

France

• French Men's Singles Championship – Frank Parker (USA) defeats Jaroslav Drobný (Egypt) 6–1, 6–2, 3–6, 5–7, 7–5
• French Women's Singles Championship – Nelly Adamson Landry (USA) defeats Shirley Fry (USA) 6–2, 0–6, 6–0

USA

• American Men's Singles Championship – Pancho Gonzales (USA) defeats Eric Sturgess (South Africa) 6–2, 6–3, 14–12
• American Women's Singles Championship – Margaret Osborne (USA) defeats Louise Brough (USA) 4–6, 6–4, 15–13

Davis Cup

• 1948 Davis Cup –  United States 5–0  Australia at West Side Tennis Club (grass) New York City, United States

• Associated Press Male Athlete of the Year – Lou Boudreau, Major League Baseball
• Associated Press Female Athlete of the Year – Fanny Blankers-Koen, Track and field^[8]