Thomas de Grey may refer to:
- Thomas de Grey (1680–1765), MP for Norfolk 1715-27
- Thomas de Grey (1717–1781), MP for Norfolk 1764-74
- Thomas de Grey, 2nd Baron Walsingham (1748–1818), MP for Wareham 1774, Tamworth 1774-80 and Lostwithiel 1780-81
- Thomas de Grey, 2nd Earl de Grey (1781–1859), British Tory politician and statesman
- Thomas de Grey, 4th Baron Walsingham (1788–1839), British peer
- Thomas de Grey, 5th Baron Walsingham (1804–1870), British peer
- Thomas de Grey, 6th Baron Walsingham (1843–1919), English politician and amateur entomologist