Tiburtino is the 6th quartiere of Rome (Italy), identified by the initials Q. VI.

It included initially only the area of San Lorenzo, but starting from 1931 it began to expand towards the Via Prenestina, incorporating part of the then Suburbio Tiburtino up to Via di Portonaccio.

Eastward, Nomentano borders with Quartiere Collatino (Q. XXII), whose boundary is entirely outlined by Via di Portonaccio.

To the south, the quarter borders with Quartiere Prenestino-Labicano (Q. VII), from which is separated by the portion of Via Prenestina between Largo Preneste and Piazzale Labicano.

To the west, Nomentano borders with Rione Esquilino (R. XV) and with Rione Castro Pretorio (R. XVIII): the boundary is marked by the Aurelian Walls up to Viale dell'Università, then by Viale dell'Università itself.