James Gardiner (12 June 1861 – 27 October 1928) was an Australian politician who served in the Legislative Assembly of Western Australia from 1901 to 1904 and from 1914 to 1921. He served as colonial treasurer under two premiers, Walter James and Henry Lefroy. Gardiner was also the inaugural state leader of the Country Party from 1914 to 1915, and briefly served as Speaker of the Legislative Assembly from March to June 1917.