David Reesor (January 18, 1823 – April 28, 1902) was an Ontario businessman and political figure.

He was born in Reesorville (later the Village of Markham), Upper Canada in 1823 to parents Abraham Reesor (1790–1831) and Anna Dettwiler (1787–1854), descended from Pennsylvania Dutch Mennonite immigrants who first settled in Lancaster County, Pennsylvania.

David was the nephew of Abraham Stouffer, founder of Stouffville, and of Peter Reesor, co-founder of Reesorville (later Markham) and Cedar Valley.

He was also a magistrate and notary public, reeve of Markham, Ontario (1851, 1856–57 and 1859–1860) and served as warden for York and Peel counties.

He was elected to the Legislative Council of the Province of Canada for King's division in 1860 and served until Confederation, when he was named to the Senate.