A separate letter released by the US defence department on Friday said a "very small number" of prisoners were under 16 years of age, the Associated Press news agency reported.
Ramzi Kassem, a law professor at City University of New York, told AP that the decision to release the names was significant. "This is completely unprecedented, we've never had access to the list," he said.
Kassem represents Amin al-Bakri, a Yemeni national, who was captured in Thailand and then sent to Bagram. In his case, a federal judge in Washington ruled that only those Bagram prisoners captured outside Afghanistan could file suit in the US.
US President Barack Obama's administration is appealing against the decision.
Bagram, north of the Afghan capital, Kabul, has been used as a detention facility by the US-led coalition in Afghanistan since the ouster of the Taliban government in December 2001.