Roscommon Abbey is a former Dominican Priory and National Monument located in Roscommon, Ireland.

Roscommon Abbey was a Dominican priory founded in 1253 by Fedlim Ó Conchobair, king of Connacht. It was plundered by Mac William de Burgo 1260. It was hit by fire in 1270 and lightning in 1308.

Roscommon Abbey was dissolved before 1578; granted to Sir Nicholas Malby in 1578 and to Francis Annesley, 1st Viscount Valentia in 1615.

Roscommon Friary is located in the southern part of Roscommon town, The church consisted of a single long aisle with nave and choir; the northern transept was added in the fifteenth century.

On his death in 1265 Fedlim Ó Conchobair was interred in the abbey and his tomb was covered by an effigial slab which can still be seen in a niche in the north-east corner of the church. The effigy was carved between 1290 and 1300 and is one of only two Irish royal effigies surviving from this period.

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  Great east window
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  Choir tomb
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  Nave seen from transept
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  North aisle
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  West gable