Monaghan County Museum, County heritage museum in Monaghan, Ireland.

Monaghan County Museum is housed at 1-2 Hill Street in Monaghan town, in two town houses dating from the 1860s that were converted for its use. Its galleries and archives document the history of County Monaghan across the whole span of human settlement, and the collection includes archaeological finds such as the Lisdrumturk Cauldron, recovered from a bog in the county.

Monaghan County Museum opened in 1974 as the first full-time, professionally staffed, local-authority-funded local museum in Ireland. It was housed in Monaghan Courthouse until a fire gutted the building in 1981; the collections were rescued and the museum moved temporarily to St Macartan's College. In 1990 it reopened at 1-2 Hill Street, two 1860s town houses converted for its use.

The museum's name appears in Irish as Músaem Chontae Mhuineacháin, and its displays trace County Monaghan's history across the whole span of human settlement. The Lisdrumturk Cauldron, found in a bog in the county, is among the archaeological objects on show. The museum is also designated by the National Museum of Ireland to collect archaeological finds.

The museum occupies two converted 1860s town houses at 1-2 Hill Street in Monaghan town centre, so it is reached on foot from the streets around the courthouse. The building is a short walk from the town's central crossroads, and the entrance is on Hill Street itself.

The Lisdrumturk Cauldron, found in a bog in County Monaghan, is among the museum's archaeological objects. The museum is also designated by the National Museum of Ireland to collect archaeological finds, and it holds early estate records such as rentals, maps and wages books.