Jacob Thompson Baker (April 13, 1847 – December 7, 1919) was an American Democratic Party politician from New Jersey who represented New Jersey's 2nd congressional district for one term from 1913 to 1915.

Baker was born near Cowan, Pennsylvania on April 13, 1847. He attended the public schools and Bucknell University. He studied law, was admitted to the bar in 1870 and commenced practice in Lewisburg, Pennsylvania.

He was chairman of the Democratic State convention in 1905. Baker moved to New Jersey and was one of the founders of Wildwood and the borough of Wildwood Crest. He was the first Mayor of Wildwood, New Jersey in 1911 and 1912, and was a delegate to the 1912 Democratic National Convention.

Baker died in Philadelphia on December 7, 1919, and was interred in Cold Spring Presbyterian Cemetery in Cold Spring, New Jersey.

Baker's home, the J. Thompson Baker House was added to the National Register of Historic Places in 1966.

• United States Congress. "J. Thompson Baker (id: B000065)". Biographical Directory of the United States Congress.
• Jacob Thompson Baker at The Political Graveyard
• J. Thompson Baker at Find a Grave