| 17th/21st Lancers | |
|---|---|
 Cap badge of the regiment | |
| Active | 1922–1993 |
| Country |  United Kingdom |
| Branch |  British Army |
| Type | Cavalry of the Line/Royal Armoured Corps |
| Role | Light Cavalry |
| Size | 550 men |
| Regimental Headquarters | Grantham |
| Nickname(s) | The Death or Glory Boys |
| Motto(s) | Death or Glory |
| March | The White Lancers |
| Commanders | |
| Colonel-in-Chief | Princess Alexandra, The Honourable Lady Ogilvy |
The 17th/21st Lancers was a cavalry regiment of the British Army. It was formed in England by the amalgamation of the 17th Lancers and the 21st Lancers in 1922 and, after service in the Second World War, it amalgamated with the 16th/5th The Queen's Royal Lancers to form the Queen's Royal Lancers in 1993.