Samuel Neilson (17 September 1761 – 29 August 1803) was an Irish businessman, journalist and politician. He was a founding member of the Society of United Irishmen and the founder of its newspaper, the Northern Star. Along with many other Protestants of Belfast he was radicalised by the French Revolution. In 1797 he was arrested and the Northern Star supressed by the Irish authorities. In prison during 1798, he took no part in the failed rebellion of that year. Later he went into exile in the United States, where he died of yellow fever.