Kentucky Derby
May 4 100th Kentucky Derby: Puerto Rican jockey Ángel Cordero Jr. wins aboard Cannonade for first of 3 Derby victories
- May 6 Oakland A's pitcher Paul Lindblad makes an errant throw in 1st inning of 6-3 loss to Baltimore, ending his record streak of 385 consecutive errorless games
- May 8 FC Magdenburg of East Germany win 14th European Cup Winner's Cup against AC Milan of Italy 2-0 in Rotterdam
- May 10 7th ABA championship: NY Nets beats Utah Stars, 4 games to 1
- May 12 28th NBA Championship: Boston Celtics beat Milwaukee, 4 games to 3
- May 17 18th European Cup: Bayern Munich beats Atletico Madrid 4-0 at Brussels
- May 18 99th Preakness: Miguel Rivera aboard Current Little wins in 1:54.6
- May 19 Stanley Cup Final, The Spectrum, Philadelphia, PA: Goaltender Bernie Parent and the Flyers shut out the Boston Bruins, 1-0, to win series 4-2, become 1st "expansion" team to win Stanley Cup; Parent named playoff MVP
- May 22 Soccer team Veendam forms
- May 26 Indianapolis 500: Johnny Rutherford claims first of his three Indy victories; first Sunday start of the event
Baseball Players
Basketball Stars
Boxers
Footballers
NFL Stars
Tennis Champions