1787 in sports

1787 in sports describes the year's events in world sport.

Boxing
Events
 * 18 January — the vacant Championship of England title was claimed by Tom Johnson following a win over William Warr at Oakingham in a 1 hour 20 minute fight or 1 hour 40 minute fight depending on the source. Johnson was then unbeaten in six known fights since 1783 and retained the title until 1791.
 * June 1786 or 5 July, depending on source — Tom Johnson defended his title against William Fry at Kingston upon Thames, winning in 30 minutes or less depending on source.
 * 19 December — Tom Johnson defended his title against Michael Ryan at Wradsbury, winning in 24 to 30 minutes or less depending on source.
 * Tom Tyne defeated the former champion George Meggs twice, but the fight locations are unknown.

Cricket
Events England
 * 21 May — opening of the original Lord's ground in Marylebone for the White Conduit Club (WCC) v Middlesex match
 * Marylebone Cricket Club (MCC) established at Lord's, chiefly by WCC members
 * Most runs – James Aylward 296
 * Most wickets – David Harris 29

Horse racing
England
 * The Derby – Sir Peter Teazle
 * The Oaks – Annette
 * St Leger Stakes – Spadille