John Winston Spencer-Churchill, 7th Duke of Marlborough (2 June 1822 - 4 July 1883) was an English statesman and nobleman.

He served as Lord President of the Council in Lord Derby's (1867-1868) government, then in Benjamin Disraeli's 1868 government. He declined the Viceroyalty of Ireland in 1874, but was later Lord Lieutenant of Ireland from 1876 to 1880.

His younger son, Lord Randolph Churchill, was a prominent Conservative politician and the father of Sir Winston Churchill.

|- style="text-align: center;" | width="30%" |Preceded by:
The Duke of Buckingham and Chandos | width="40%" style="text-align: center;" |Lord President of the Council
1867–1868 | width="30%" |Succeeded by:
The Earl of Ripon

|- style="text-align: center;" | width="30%" |Preceded by:
The Duke of Abercorn | width="40%" style="text-align: center;" |Lord Lieutenant of Ireland
1876–1880 | width="30%" |Succeeded by:
The Earl Cowper