The caucus made the announcement at a Capitol Hill press conference Wednesday where Lee accepted the gavel from outgoing Chairwoman Carolyn Kilpatrick.
Lee, just elected to her 7th term, said she looked forward to working with President-elect Barack Obama in advancing goals of justice and equality.
"We have many, many challenges, but those challenges do present historic opportunities," Lee said.
Lee's bid for the chair was unopposed.
The Congressional Black Caucus formed in the 1970's and began with 13 members. Among them was current mayor of Oakland Ron Dellums. Lee started her career working as an aids to Dellums.
Wednesday, Kilpatrick praised Lee as a "stalwart for human rights, global peace and social justice."