The Supreme Court Justice was welcomed with a traditional investiture ceremony attended by the president and vice president.
Three months after Chief Justice John Roberts conducted her first official swearing-in, Jackson was formally sworn in as the first black woman to serve on the Supreme Court.
Roberts and the seven other justices were in attendance for Friday's ceremony, along with her husband Patrick Jackson, Attorney General Merrick Garland and Solicitor General Elizabeth Prelogar, who represents the US government in cases at the high court.
Jackson took the oath again in June when she became the new justice.
US Supreme Court Justice Ketanji Brown Jackson speaks with Chief Justice John Roberts on the steps of the US Supreme Court, immediately following the investiture ceremony of Justice Jackson, in Washington, DC, September 30, 2022.Jackson sat in the chair that once belonged to John Marshall, who was one of the most influential members of the court.
The Senate voted 53-47 to confirm Jackson in April.
She will hear her first oral argument as a justice on Monday.
Nearly 6 in 10 Americans think the Supreme Court is out of touch, according to a new poll. The court's decision in June to overturn the federal constitutional right to abortion caused a lot of controversy.
A majority of Americans agree with term limits for Supreme Court justices.