| Building Name: | Sidi Lakhdar Mosque مسجد سيدي الاخضر |
| Location: | Al-Jazzarin neighborhood Constantine, Algeria |
| Map Type: | Algeria |
| Map Relief: | 1 |
| Coordinates: | 36.3676°N 6.6139°W |
| Religious Affiliation: | Islam |
| Province: | Constantine |
| District: | Constantine |
| Municipality: | Constantine |
| Architecture Type: | mosque |
| Architecture Style: | Islamic, Ottoman style |
| Year Completed: | 1743 [1] |
| Capacity: | 500 worshippers |
| Dome Quantity: | 1 |
| Minaret Quantity: | 1 |
Sidi Lakhdar Mosque (ar|مسجد سيدي الاخضر ), or Djamâa Lakhdar is a mosque located in Constantine, Algeria.
It is mainly characterised by its curved marble columns and its admirable sculpted capitals.the sanctuary of the mosque, which has a rectangular shape, is located on the first floor and can be entered through two open doors in the wall opposite the mihrab and its "minbar" of carved wood,it was classified in 1905 and its decoration remains a witness on the history of its construction through the roof and wooden columns.
Sidi Lakhdar Mosque is located in the Al-Jazzarin neighborhood, and it was built in 1743 by the Bey Hussein bin Hussein, known as Bouhanak, who was buried in this mosque after his death. In 1913 The mosque, which witnessed many scholarly sessions of Sheikh Abdelhamid Ben Badis he installed his seminary and marked the center of his foundation "Algerian Muslim Congress" (CMA),