A federal judge sentenced Ahmed Abu Khattala to 22 years in prison for the attack on the US diplomatic compound in Benghazi, U.S. media reported.
The U.S. Department of Justice statement described him the 47-year-old as the "mastermind behind the deadly 2012 attacks on U.S. government installations in Benghazi."
Ahmed Abu Khattala was convicted last November by a jury on four counts for the attack on a CIA compound that killed four Americans, including Ambassador Christopher Stevens, charges included conspiring to provide material support to terrorists.
US special forces arrested Abu Khatalla, at his home in Libya in June 2014, and was transferred to the United States aboard a US naval vessel.
Abu Khattala plead innocent of the charges against him which included 18 counts of conspiracy, support for terrorism, murder, murder and destruction of U.S. facilities. The trial began in Washington more than a year ago, during which the court was able to review a series of video surveillance tapes and phone call records.