Albert Barnes (December 1, 1798 – December 24, 1870) was an American theologian, born in Rome, New York. He graduated from Hamilton College, Clinton, New York, in 1820, and from Princeton Theological Seminary in 1823. Barnes was ordained as a Presbyterian minister by the presbytery of Elizabethtown, New Jersey, in 1825, and was the pastor successively of the Presbyterian Church in Morristown, New Jersey (1825–1830), and of the First Presbyterian Church of Philadelphia(1830–1868).
Albert Barnes held a prominent place in the New School branch of the Presbyterians during the Old School-New School Controversy, to which he adhered on the division of the denomination in 1837; he had been tried (but not convicted) for heresy in 1836, mostly due to the views he expressed in Notes on Romans (1835) of the imputation of the sin of Adam, original sin and the atonement; the bitterness stirred up by this trial contributed towards widening the breach between the conservative and the progressive elements in the church.
During the Old School-New School split in the Presbyterian Church in the United States of America, Barnes allied himself with the New School Branch. He served as moderator of the General Assembly to the New School branch in 1851.  He was an eloquent preacher, but his reputation rests chiefly on his expository works, which are said to have had a larger circulation both in Europe and America than any others of their class.
Of the well-known Notes on the New Testament, it is said that more than a million volumes had been issued by 1870. The Notes on Job, the Psalms, Isaiah and Daniel were also popularly distributed. The popularity of these works rested on how Barnes simplified Biblical criticism so that new developments in the field were made accessible to the general public. Barnes was the author of several other works, including Scriptural Views of Slavery (1846) and The Way of Salvation (1863). A collection of his theological works was published in Philadelphia in 1875.
While serving as pastor at the First Presbyterian Church of Philadelphia, Barnes became the President of the Pennsylvania Bible Society (located at 7th and Walnut) in 1858 – a position he served until his death in 1870. He served at First Presbyterian Church of Philadelphia until 1868. He was then granted the title Pastor Emeritus. 
In his famous 1852 oratory, "What to the Slave is the Fourth of July?", Frederick Douglass quoted Barnes as saying: "There is no power out of the church that could sustain slavery an hour, if it were not sustained in it."
Barnes died in Philadelphia on December 24, 1870.
The Presbyterian Historical Society in Philadelphia, Pennsylvania, has a collection of Rev. Barnes’ original manuscripts, notes, sermons and lectures.
- Chisholm, Hugh, ed. (1911). "Barnes, Albert". Encyclopædia Britannica (11th ed.). Cambridge University Press.
Wikiquote has a collection of quotations related to: Albert Barnes
- "The Way of Salvation," the published form of the 1829 sermon that precipitated heresy charges against Barnes by Old School Presbyterians
- Albert Barnes – New Testament Notes
- Short Biography of Barnes