Sinnett may refer to:
Alfred Percy Sinnett (1840–1921), English author and Theosophist Lawrence C. Sinnett (1888–1962), Seaman in the United States Navy, Medal of Honor recipient Thomas P. Sinnett (1880–1967), member of the Illinois House of Representatives Sinnett Octagon House, historic octagonal house in Muscatine, Iowa built in 1855 The Mahatma Letters to A.P. Sinnett, book published in 1923 by A. Trevor Barker
See also Scinet (disambiguation) Sennet (disambiguation) Sennett (disambiguation) Sinnott