| Honorific Prefix: | The Right Honourable |
| The Lord De L'Isle and Dudley | |
| Birth Name: | Philip Charles Shelley Sidney |
| Birth Date: | 11 March 1800 |
| Parents: | Sir John Shelley-Sidney, 1st Baronet Henrietta Hunloke |
| Office: | Member of Parliament for Eye |
| Alongside: | Sir Edward Kerrison |
| Term Start: | 19 October 1829 |
| Term End: | 14 March 1831 |
| Predecessor: | Sir Miles Nightingall Sir Edward Kerrison |
| Successor: | Sir Edward Kerrison William Burge |
| Office1: | Member of the House of Lords |
| Status1: | Lord Temporal |
| Term Start1: | 13 January 1835 |
| Predecessor1: | Peerage created |
| Term End1: | 4 March 1851 |
| Successor1: | The 2nd Baron De L'Isle and Dudley |
| Party: | Tory |
| Alma Mater: | Eton College Christ Church, Oxford |
| Relatives: | William IV (father-in-law) |
Philip Charles Shelley Sidney, 1st Baron De L'Isle and Dudley (11 March 1800 – 4 March 1851), was a British Tory politician.
Sidney was the only son of Sir John Shelley-Sidney, 1st Baronet, and Henrietta Hunloke. The poet Percy Bysshe Shelley was his first cousin. He was educated at Eton and Christ Church, Oxford.
On 13 August 1825, he married Lady Sophia FitzClarence, illegitimate daughter of King William IV and his mistress, the actress Dorothea Jordan. Lord and Lady De L'Isle and Dudley had four children:
Sidney represented Eye in the House of Commons from 1829 to 1831 and also served as an equerry to his father-in-law from 1830 to 1835 and as Surveyor-General of the Duchy of Cornwall from 1833 to 1849. In 1835, fourteen years before he succeeded his father, he was raised to the peerage as Baron De L'Isle and Dudley, of Penshurst in the County of Kent.
Lord de L'Isle and Dudley died in March 1851, aged 50, and was succeeded in his titles by his son Philip.