Events from the year 1331 in Ireland.

• Lord: Edward III

• "A hosting by the Connachtmen, both Foreigner and Gaidhel, into Munster, against Mac Conmara. Pledge and sway were gained by them on Mac Conmara. A church was burned by a party of the host, wherein were two score and one hundred persons, both noble and base and two priests were of them and those all were burned."
• "Ten of the people of Donnchadh the Swarthy, son of Mael-Shechlainn Carrach Mac Diarmata, were drowned on Loch-Teiched."
• 21 January – Parliament at Dublin
• 27 February – Anthony de Luci appointed justicier
• 3 March – William de Burgh, Earl of Ulster, appointed lieutenant. Ordinances for Conduct of Irish government includes a decree that there should be one law for Irish and Anglo-Irish, except for betaghs
• 21 April – Irish raid and capture Arklow
• 25 April – Irish raid Tallaght
• Irish raids in County Wexford.
• 1 July – Irish Parliament meets at Dublin
• August Irish raid and capture Ferns
• 16 August – Earl of Desmond captured by Justiciar at Limerick
• Edward III plans expedition to Ireland for 1332
• September Henry de Mandeville arrested
• Walter de Burgh defeats Tommaltach Mac Diarmata in Moylurg
• November Walter de Burgh arrested and imprisoned by the Earl of Ulster

• 4 October – James Butler, 2nd Earl of Ormonde, Lord Justice of Ireland (died 1382).

• Tadhg mac Cathal mac Domnall Ua Conchobair rested in Christ

• "The Annals of Ireland by Friar John Clyn", edited and translated with an Introduction, by Bernadette Williams, Four Courts Press, 2007. ISBN 978-1-84682-034-2, pp. 240–244.
• "A New History of Ireland VIII: A Chronology of Irish History to 1976", edited by T. W. Moody, F.X. Martin and F.J. Byrne. Oxford, 1982. ISBN 0-19-821744-7.
• http://www.ucc.ie/celt/published/T100001B/index.html
• http://www.ucc.ie/celt/published/T100005C/index.html
• http://www.ucc.ie/celt/published/T100010B/index.html