Septimus Alfred Stephen (8 May 1842 – 28 August 1901) was an Australian politician, solicitor and founder of the lawfirm Stephen, Jaques and Stephen.
The Stephen family is a prominent legal dynasty in Australia. He was born in Sydney, the seventh son of Sir Alfred Stephen KCMG CB (1802–1894), who would later become Chief Justice of NSW and Lieutenant-Governor of NSW, and Eleanor Martha Pickard. He became a solicitor's clerk in 1858 and qualified as a solicitor in 1864. In 1882 he was elected to the New South Wales Legislative Assembly for Canterbury, serving until his appointment to the Legislative Council in 1887. He was severely affected by the 1890s drought, which damaged many of his investments in Queensland. He left the Legislative Council in 1900 and died at Woodhay in Hampshire the following year.