Col. John Stevens, III (1749 - March 6, 1838) was a lawyer, engineer, and inventor.

Born in New York, New York, the son of John Stevens (1715-1792), secretary to Governor Livingston of New York, and his wife Elizabeth Alexander.

He graduated King’s College (which became Columbia University) in May 1768

At age 27 he was appointed a Captain in Washington's army, and was afterwards treasurer of New Jersey, and bought at public auction from the state of New Jersey land which had been confiscated from a Tory landowner. The land, described as "William Bayard's farm at Hoebuck" comprised approximately what is now the city of Hoboken.

In 1802 he built a screw-driven steamboat, and in 1809 he built the Phoenix, an ocean-going steamboat. On October 11, 1811 Stevens' ship the Juliana, began operation as the first steam-powered ferry (service was between New York, New York, and Hoboken, New Jersey). He then built the first steam locomotive in the United States in 1825. He helped develop United States patent law.

On 17 October 1782 he married Rachel Cox, a descendant of the Langfeldts who originally settled New Brunswick, New Jersey.

They had nine children:

• John Cox Stevens (1785-1857), first commodore of the New York Yacht Club
• Robert Livingston Stevens (1787-1856)
• Edwin Augustus Stevens (1795-1868), founder of Stevens Institute of Technology
• James Alexander Stevens
• Elizabeth Juliana Stevens
• Mary Stevens
• Harriet Stevens
• Esther Cox Stevens
• Catherine Sophia Stevens