Otto Dietze (Latvian: Oto Dice) (1 July 1833, Chemnitz – 17 October 1890, Riga) was a German-born architect.
He is most noted for his work in Jelgava from 1863–1872.
He designed the Latvian pastor St.
Peter's House (1864), the railway station and residential houses.In Kuldiga he rebuilt the ancient brick bridge across the Venta River (1874).