James Cosgrave (died 18 April 1936; surname also spelt as Cosgrove) was an Irish nationalist politician, one of the few parliamentarians who served in the House of Commons of the United Kingdom and in Dáil Éireann.
Born in Skehanagh, Eyrecourt, County Galway, he was returned unopposed as Member of Parliament for East Galway in the 4 December 1914 by-election for the Irish Parliamentary Party on the death of John Roche.
He did not contest the 1918 general election, and the seat was won by Liam Mellows of Sinn Féin.
He successfully ran as an Independent Nationalist at the 1923 general election. At the 1927 June and September elections, he unsuccessfully ran as a National League Party candidate.
In later years, he was associated with Fianna Fáil. He was later a member of Galway County Council and chairman of Ballinasloe Mental Hospital Committee.
Cosgrave remarried in 1923 and moved to Dublin, where he died at his residence at Baggot House, 91 Lower Baggot St. He is buried in Quansboro, Killimor, County Galway.