Aaron Henry (July 2, 1922 – May 19, 1997) was an American civil rights leader, politician, and head of the Mississippi branch of the NAACP. He was one of the founders of the Mississippi Freedom Democratic Party, which tried to seat their delegation at the 1964 Democratic National Convention.

Aaron Henry was born in Dublin, Mississippi to parents Ed and Mattie Henry, who worked as sharecroppers. While growing up, he worked on the Flowers brothers' plantation, which was twenty miles east of Clarksdale in Coahoma County. Henry detested everything about growing cotton because of the hardships that it brought upon the African Americans working on the plantation. Henry's parents believed education to be essential for the future of Henry and his family; they enabled him to attend the all-black Coahoma County Agricultural High School. After graduating from high school, Henry worked as a night clerk at a motel to earn money for college, but ended up enlisting in the Army. Three years in the army taught him that racial discrimination and segregation were common, many instances of which he described to Robert Penn Warren; these were used in his book Who Speaks for the Negro?. At the same time, his Army years confirmed Henry's feelings that segregation was worse in his home state. He decided that he would work for equality and justice for black Americans as soon as he returned home after the war. When he returned to Clarksdale in 1946, a Progressive Voters' League had been formed to work to implement the 1944 Supreme Court decision abolishing white primaries.

Henry noted that the Mississippi legislature had exempted returning veterans from paying the poll tax. This had been a barrier to voter registration and voting by Blacks, who were often cash poor and found it hard to pay such fees. Under the poll tax laws, a person had to have paid his poll tax for two years prior to the time that he voted. Therefore, Henry tried to get black veterans to go down to the courthouse and register to vote. However, several Black veterans were unable to register.

When Henry went to the circuit clerk's office to register, he was also rejected. The clerk asked Henry to bring a certificate showing that he was exempt from the poll tax. After he brought the certificate, the clerk said that Henry still needed to pass various tests to show that he was qualified to vote; such as a literacy or comprehension test, all administered subjectively by the clerk. After he successfully read several sections of the state constitution and passed other tests, Henry finally was able to register to vote.

He used the G.I. Bill, a law that provided educational benefits for World War II veterans, to enroll in the pharmacy school at Xavier University. When he graduated in 1950 with a pharmaceutical degree, he married Noelle Michael and started his own pharmacy business.

As a businessman in Clarksdale, he became involved in local and state activities, particularly events such as African-American voter registration. He decided to organize an NAACP branch in Clarksdale, and was encouraged by W.A. Higgins, an NAACP member and principal of the Black high school. A catalyst was the acquittal of two white men charged with raping two Black girls.

The NAACP national headquarters encouraged the two men to found the Mississippi chapter in Clarksdale. In 1959, Henry was elected president of the Mississippi organization, and served in the NAACP for decades. He became close friends with Medgar Evers, who had worked as a secretary for the NAACP in 1950. He continued to be active in civil rights, based in Jackson. On June 12, 1963, Evers was assassinated in his driveway at home. Henry was shocked and outraged.

In 1951, Henry was a founding member of the Regional Council of Negro Leadership (RCNL). The main leader and head of the organization was T.R.M. Howard, a prominent black surgeon, fraternal organization leader, and entrepreneur in the all-black town of Mound Bayou, Mississippi.