Sir William Fitzherbert KCMG (15 August 1810 – 6 February 1891) was a New Zealand politician.

He also served as Colonial Treasurer (Minister of Finance) for the duration of Frederick Weld's premiership.

The Palmerston North suburb of Aokautere was once named after Fitzherbert, as he had promoted settlement of the Manawatu.

He was buried at Lower Hutt cemetery on 10 February next to his late wife, who had died on 21 August 1886.

The peak of the Eastern Hills dividing Naenae and Wainuiomata and its television relay mast is named Mount Fitzherbert.