Mbiriizi is a town in the southern part of the Central Region of Uganda. It is the administrative center of Lwengo District.
Mbiriizi is approximately , by road, west of Masaka, the nearest large city, on the all-weather highway between Masaka and Mbarara. This is approximately , by road, south-west of Kampala, the capital and largest city of Uganda. The coordinates of the town are 00 23 33S, 31 27 30E (Latitude: -0.3927; Longitude:31.4585).
The town lies along the Masaka-Mbarara Road which connects to Kampala, Uganda's capital to the east and Kigali, the capital city of Rwanda to the southwest.
The 2024 documentary Memories of Love Returned, by Ugandan American filmmaker and actor Ntare Guma Mbaho Mwine, documents the life and work of Mbiriizi photographer Kibaate Aloysius Ssalongo.
The following points of interest lie within the town limits or near the town edges: (a) The headquarters of Lwengo District Administration (b) Finance Trust Bank (c) Offices of Lwengo Town Council (d) Offices of Electoral Commission Lwengo District (e) Masaka-Mbarara Road, which passes through the middle of town in a general east/west direction (f) Mbiriizi Advanced Primary School.