Silas Zephaniah Landes (15 May 1842-23 May 1910) was a member of the US House of Representatives (D-IL 16) from 4 March 1885 to 3 March 1889, succeeding Aaron Shaw and preceding George W. Fithian. Born in Augusta County, Virginia, he became a lawyer in Mount Carmel, Illinois in 1863 and served as Wabash County prosecuting attorney from 1872 to 1884, in Congress, and as a judge from 1891 to 1897.