| Caernarvonshire | |
|---|---|
| Former county constituency for the House of Commons | |
| 1918–1950 | |
| Created from | Arfon and Eifion |
| Replaced by | Caernarvon and Conway |
| 1542–1885 | |
| Replaced by | Arfon and Eifion |
Caernarvonshire was a constituency of the House of Commons of the Parliament of England, then of the Parliament of Great Britain from 1707 to 1800, and of the Parliament of the United Kingdom from 1801 to 1885 and from 1918 until 1950. It elected one Member of Parliament (MP) by the first past the post system.