Donald Lawrence O'Toole (August 1, 1902 – September 12, 1964) was an American lawyer and politician who served eight terms as a United States representative from New York from 1937 to 1953.

Born in Brooklyn, he attended public and parochial schools, graduated from St. James Academy in Brooklyn in 1916, and from the law department of Fordham University in 1925.

He was a postgraduate student at Columbia University and New York University, then was admitted to the bar in 1927, commencing practice in New York City.

A resident of Brooklyn, he died in Ocala, Florida, in 1964.

Interment was in Holy Cross Cemetery, Brooklyn.