Alexander Porter (June 24, 1785 – January 13, 1844) was an attorney, politician, and planter, who served as United States Senator from Louisiana from 1833 to 1837.

Born in County Donegal, Ireland, Alexander Porter immigrated to the U.S. in 1801 with an uncle, who settled in Nashville, Tennessee.

Porter returned to St. Mary Parish to practice law and manage his plantation, Oaklawn.

He was again chosen by the legislature for the U.S. Senate, for the term beginning March 4, 1843; but he did not take his seat due to poor health.

His remains were interred in Nashville City Cemetery, the location of the grave of his young wife, Evilina (Baker) Porter (1797–1819).