|San Leone Magno dei Fratelli Maristi|
|English name:||St Leo the Great of the Marist Brothers|
|Dedication:||Leo the Great|
|Address:||Piazza di Santa Costanza 1|
San Leone Magno dei Fratelli Maristi is a public dependent chapel of the parish of Sant'Agnese fuori le Mura , and is at Piazza di Santa Costanza 1, just south-west of the church in the Trieste district.
It is the chapel of the Instituto San Leone Magno, a large private school run by the Marist Brothers, but is advertised as open for public worship despite being close to the parish church.