Protestant Irish Nationalists are adherents of Protestantism in Ireland who also support Irish nationalism. Protestants have played a large role in the development of Irish nationalism since the eighteenth century, despite most Irish nationalists historically being from the Irish Catholic majority, as well as most Irish Protestants usually tending toward unionism in Ireland. Protestant nationalists (or patriots, particularly before the mid-19th century) have consistently been influential supporters and leaders of various movements for the political independence of Ireland from Great Britain. Historically, these movements ranged from supporting the legislative independence of the Parliament of the Kingdom of Ireland, to a form of home rule within the United Kingdom of Great Britain and Ireland, to complete independence in an Irish Republic and (since the partition of Ireland) a United Ireland.

Despite their relatively small numbers, individual Protestants have made important contributions to key events in Irish nationalist history, such as Wolfe Tone during the 1798 rebellion, Charles Stewart Parnell and the Home Rule movement, and Erskine Childers and the 1916 Easter Rising.

In Northern Ireland, the vast majority of Ulster Protestants are unionist and vote for unionist parties. In 2008, only 4% of Protestants in Northern Ireland thought the long-term policy for Northern Ireland should be unification with the Republic of Ireland, whereas 89% said it should be to remain in the United Kingdom.

All the various denominations of Protestantism in Ireland have had members involved in nationalism. The Anglican Church of Ireland and the Presbyterian Church of Ireland are the largest Protestant churches, and this remains the situation across the island of Ireland. The largest Protestant denomination is the Church of Ireland (having roughly 365,000 members, making up around 3% of the population of the Republic of Ireland, 15% of Northern Ireland, and 6.3% of the whole of Ireland), followed by the Presbyterian Church, with a membership of around 300,000, accounting for 0.6% of people in the Republic and 20% in Northern Ireland (6.1% of Ireland's population).