Ottaviano Nelli (1375–1444) was an Italian painter of the early Quattrocento.
He was born in Gubbio, and active there and in Perugia (1400), Urbino, Assisi, and Foligno. Among his pupils was his brother Tommaso, Domenico Di Cecco di Baldi, Giovanni Pintali, Giacomo Di Bedo, and Ubaldo Di Matteo.