Sir Walter Clarke Buchanan (20 June 1838 – 19 July 1924) was a New Zealand politician who became a member of the Reform Party that formed in 1909.

Despite never being appointed as a minister, he was an influential politician and a strong advocate for farming interests.

[3] In the four general elections between 1881 and 1890, he always beat Henry Bunny,[4][5][6][7] who had represented the Wairarapa electorate continuously since an 1865 by-election.

[8] In the House, he was a staunch conservative voice, and a diehard opponent of the Liberal government of Richard Seddon.

[9] Despite his long experience in politics, he was never appointed a Minister (partly because the Liberal Party was in power as from 1891 to 1914).