Federal Judge Loretta Preska cited the need for deterrence in issuing the 33-year, nine-month sentence. U.S. prosecutors had asked a Manhattan judge to give Abdiwali Abdiqadir Muse nearly 34 years in prison.
His lawyers had asked for the minimum term, 27 years.
Muse pleaded guilty last year to federal charges alleging his crew of armed pirates commandeered a merchant ship in the Indian Ocean and took its captain hostage. A tense standoff ended when Navy sharpshooters killed three of Muse's men and freed captain Richard Phillips, of Underhill, Vt.
The case was part of a stepped-up effort to stem a wave of 21st-century piracy using 19th-century maritime laws.