Pierse Long (1739 – April 13, 1789) was an American merchant from Portsmouth, New Hampshire. He served as a colonel of the Continental Army in the Revolutionary War and served as a New Hampshire delegate to the Confederation Congress in 1785 and 1786. After his apprenticeship, Pierse became a merchant in his own right, exporting timber to the West Indies and importing goods from England and Ireland. He prospered in business and became active in the militia and in civic affairs. Long died at home in Portsmouth on April 13, 1789 and is buried in the Proprietor's Burying Ground there.