- Jan 1 Massive Chinese/North Korean assault on UN-lines
- Jan 1 37th Rose Bowl: #9 Michigan beats #5 California, 14-6
- Jan 1 17th Sugar Bowl: #7 Kentucky beats #1 Oklahoma, 13-7
- Jan 1 17th Orange Bowl: #10 Clemson beats #15 Miami (FL), 15-14
- Jan 2 Philip Barry's "Second Threshold," premieres in NYC
- Jan 3 9 Jewish Kremlin physicians "exposed" as British/US agents
- Jan 4 Korean War: Chinese forces recapture Seoul
- Jan 6 "Pardon Our French" closes at Broadway Theater NYC after 100 performances
- Jan 6 Indianapolis Olympians beat Rochester Royals, 75-73 in NBA-record 6 overtimes; also the longest game in NBA history
- Jan 6 Ganghwa massacre: Hundreds of South Korean communist sympathisers are slaughtered
- Jan 8 Thought extinct since 1615, a Cahow (the Bermuda petrel) is rediscovered in Bermuda
NHL Record
Jan 10 Maurice Richard scores his 16th career hat trick in the Montreal Canadiens' 3-0 win over NY Rangers to bring his career total to 274 goals; passes Howie Morenz as NHL's #2 all-time leading goal scorer
Boxing Title Fight
Jan 12 Ezzard Charles TKOs Lee Oma in 10 for heavyweight boxing title
- Jan 13 German general Christian Hansen freed early from Dutch prison
NFL Pro Bowl
Jan 14 1st NFL Pro Bowl, Los Angeles Memorial Coliseum: American Conference beats National Conference, 28-27; MVP: Otto Graham, Cleveland Browns, QB
- Jan 15 "Cloud of Death" rolls down Mount Lamington, New Guinea kills 3-5,000
- Jan 15 Supreme Court rule "clear & present danger" of incitement to riot is not protected speech & can be a cause for arrest
- Jan 15 Ilse Koch, also known as "The Bitch of Buchenwald", is sentenced to life imprisonment by a West German court
- Jan 16 Viet Minh offensive against Hanoi
- Jan 16 World's largest gas pipeline opens (Brownsville Texas, to 134th St, New York City)
- Jan 17 China refuses ceases-fire in Korea
- Jan 18 1st use of lie detector in the Netherlands
- Jan 18 Hermann Flake sentenced to death due to "hate campaign against GDR"
- Jan 18 NFL rules tackles, guards & centers ineligible for forward pass
- Jan 18 NFL takes control of failing Baltimore Colts
- Jan 18 1951 NFL Draft: Kyle Rote from SMU first pick by New York Giants
- Jan 18 Mount Lamington in Papua New Guinea erupts, killing 2,942 people
- Jan 22 Bollingen Prize for poetry awarded to Johncrowe Ransom
- Jan 22 Fidel Castro is ejected from a Winter League baseball game after hitting a batter
- Jan 23 3rd Emmy Awards: Alan Young Show, Alan Young and Gertrude Berg win
- Jan 24 Dutch government Drees-van Schaik resigns
- Jan 26 Mel Ott & Jimmie Foxx elected to Baseball Hall of Fame
Musical Finale
Jan 27 Leonard Bernstein's musical "Peter Pan", starring Jean Arthur and Boris Karloff, closes at Imperial Theater, NYC, after 320 performances
- Jan 27 US begins 126 nuclear tests at Nevada Test Site
- Jan 28 US performs nuclear test at Nevada Test Site
- Jan 28 "La Vie Commence Demain" the 1st X-rated movie, depicting artificial insemination, opens in London
- Jan 29 "Where's Charley?" opens at Broadway Theater NYC for 56 performances
- Jan 29 Baseball signs 6 year All-Star pact for TV-radio rights for $6 million
- Jan 30 Belgium refuses to allow communists to make speeches on radio
- Jan 31 Australian Championships Women's Tennis: Nancye Wynne Bolton beats Thelma Coyne Long 6-1, 7-5 for her 6th and last Australian singles crown
- Jan 31 Australian Championships: American Dick Savitt wins his only Australian title; beats Ken McGregor of Australia 6-3, 2-6, 6-3, 6-1