David Sewall (October 7, 1735 – October 22, 1825) was a Massachusetts attorney and judge.
Born in York, Maine (then part of Massachusetts), son of Samuel Sewall and Sarah Batchelder, Sewall received an A.B. from Harvard College in 1755 and read law to enter the Bar in 1760. He had a private practice in York 1760, and became register of probates for York County in 1766, and a justice of the peace for the Province of Massachusetts Bay in 1767. He was a member of the York Committee of Correspondence, and of the Legislative Council of Massachusetts from 1776-1777. From 1777-1789, he was a Justice of the Massachusetts Supreme Judicial Court, during which time he also served as a Delegate to the Massachusetts Constitutional Convention in 1779-1780. He was a charter member of the American Academy of Arts and Sciences (1780).
Sewall was nominated by President George Washington on September 24, 1789, to be the first judge of the United States District Court for the District of Maine, a seat which had been created by 1 Stat. 73. Confirmed by the United States Senate on September 26, 1789, he received his commission the same day and held that office until his resignation on January 9, 1818. He then returned to private practice in York until 1825. Sewall was elected a member of the American Antiquarian Society in 1814.