Harry Gordon Jackett (6 July 1887 – 3 May 1951) was an Australian politician and a member of the New South Wales Legislative Assembly from 1935 and 1938 and from 1941 until his death.
Jackett was born in Laura, South Australia and educated in Adelaide.
His father owned a flour milling business which Jackett inherited and enlarged.
Jackett was elected to the New South Wales Parliament as the United Australia Party member for Burwood at the 1935 state election, succeeding the retiring UAP member Thomas Henley.
Mitchell won the seat but Jackett regained it as an Independent UAP candidate in 1941.