- May 2 Leicester City win the English Premier League title after starting the season at 5,000-1 odds
- May 2 World Snooker Championship, Crucible Theatre, Sheffield: Mark Selby of England beats China's Ding Junhui, 18-14 for his second world crown
- May 3 Ted Cruz suspends his campaign to be the Republican Presidential nominee
- May 4 Ohio Governor John Kasich bows out of the race for US Republican Presidential nominee
- May 5 Fort McMurray wildfires: Canadian province of Alberta declares a state of emergency as evacuation of 80,000 people continues
- May 7 142nd Kentucky Derby: Nyquist ridden by Mario Gutierrez wins in 2:01.31
- May 8 Sadiq Khan (L) is elected Mayor of London, - 1st Muslim mayor of a major Western city
Election of Interest
May 9 Rodrigo Duterte wins Philippine presidential election, promising war on drug trade and killing of criminals

Rodrigo Duterte
Event of Interest
May 9 Boris Johnson resigns as Mayor of London, succeeded by Sadiq Khan

Boris Johnson
- May 10 Indian fertility clinic announces that a 70 year old woman has successfully gave birth to a baby boy
Event of Interest
May 11 Brazilian senate votes to suspend President Dilma Rousseff and put her on trial for budgetary violations

Dilma Rousseff
- May 12 Michel Temer, former vice-president, becomes Brazilian interim President after a vote to impeach Dilma Rousseff
- May 14 61st Eurovision Song Contest: Ukraine's Jamala wins singing "1944"
Event of Interest
May 14 Gabriel Medina becomes the first surfer ever to land the move "Backflip" in competition

Gabriel Medina
- May 15 PGA Players Championship, TPC at Sawgrass: World #1 and reigning PGA Champion Jason Day of Australia leads wire-to-wire to win by 4 strokes ahead of Kevin Chappell
- May 19 EgyptAir flight MS804 goes missing over the Mediterranean on route Paris to Cairo
- May 21 Mullah Akhtar Muhammad Mansour, leader of the Afghan Taliban is reportedly killed by a US drone in Pakistan
- May 21 141st Preakness Stakes: Kent Desormeaux aboard Exaggerator wins in 1 minute 58 seconds
- May 21 On same card, American boxer Jermell Charlo KOs John Jackson in 8th to claim vacant WBC super welterweight title, and Jermall Charlo beats Austin Trout on points to retain IBF version; first twins to hold world championships in same weight division
- May 21 English FA Cup Final, Wembley Stadium, London: Manchester United beats Crystal Palace, 2-1 (a.e.t.); Jesse Lingard scores 110' winner
- May 22 69th Cannes Film Festival: "I, Daniel Blake," directed by Ken Loach wins the Palme d'Or
Event of Interest
May 22 US President Barack Obama arrives in Vietman for a 3 day tour

Barack Obama
- May 22 Independent Alexander Van der Bellen defeats Freedom Party's Norbert Hofer by just 31,000 votes to become President in Austrian elections
Television Premiere
May 22 TV series "Preacher", developed by Evan Goldberg, Sam Catlin, and Seth Rogen, premieres on AMC

Seth Rogen
- May 22 The Tradition Senior Men's Golf, Greystone G&CC: Germany's Berhard Langer wins sixth of 13 Champions Tour majors by 6 strokes from Olin Browne
- May 23 Chinese archaeologists announce findings of earliest use of barley in China to make beer, Shaanxi province 3400-2900 BC
- May 24 Kaduna state in Nigeria declares a state of emergency due to 'Tomato Ebola', as moth destroys 80% of tomato crops
Event of Interest
May 24 Bill Cosby is ordered to stand trial in a sexual assault case in Norristown

Bill Cosby
- May 27 3 ships in 3 days sink carrying immigrants across the Mediterraneann, drowning over 700 people
- May 28 Harambe, a gorilla form Cincinnati Zoo, is shot after dragging a 3 year old boy who had slipped into its enclosure
- May 28 UEFA Champions League Final, Milan: Real Madrid beats cross-town rivals Atlético Madrid, 5–3 on penalties after a 1–1 draw at the end of extra time; record-extending 11th title
- May 29 IPL Cricket Final, M. Chinnaswamy Stadium, Bangalore: Sunrisers Hyderabad beat Royal Challengers Bangalore by 8 runs; David Warner 69 (38)
- May 29 Senior PGA Championship Men's Golf, GC at Harbor Shores: Rocco Mediate wins his lone career major title by 3 strokes from Colin Montgomerie of Scotland
- May 30 Former Chad dictator Hissène Habré convicted of crimes against humanity by the Extraordinary African chambers, 1st ex-head of state convicted of the charge