Mortimer Sackville-West, 1st Baron Sackville (22 September 1820 – 1 October 1888), was a British peer and court official.

Sackville-West was the fourth son of George Sackville-West, 5th Earl De La Warr, and Elizabeth Sackville, 1st Baroness Buckhurst, younger daughter and co-heir of John Sackville, 3rd Duke of Dorset.

On the death of his kinsman Charles Sackville-Germain, 5th Duke of Dorset, in 1843, the dukedom and its subsidiary titles became extinct.

[1] The peerage was created with special remainder, failing heirs male of his body, to his younger brothers Lionel and William Edward.

He died in 1888, aged 68, and was succeeded in the barony according to the special remainder by his younger brother Lionel.