State Department spokesman Adam Ereli acknowledged Thursday that the department has been contacted about the circumstances of the Libyan's incarceration.
"We have passed along these concerns to the appropriate officials in the United Kingdom for a response," he said.
A Scottish court convicted Abdel Basset Ali al-Megrahi of the bombing in 2001 and sentenced him to life imprisonment. A second Libyan was acquitted.
Pictures of Megrahi's surroundings at the Glasgow prison have appeared in the British media.
News of the World said the facilities rival those of a four-star hotel.
"They include his own kitchen and shower room, a sitting room and bedroom with en-suite toilet," the newspaper said.
The Daily Mail wrote that the conditions are in contrast to those experienced by the rest of the prisoners.
"Obviously, this is not justice or punishment, this is just part of a deal," said Dan Cohen, of Cape May Courthouse, N.J. Cohen is the father of Theodora Cohen, one of the 270 persons who died in the Dec. 21, 1988, explosion over Lockerbie, Scotland.
Meanwhile, the State Department renewed a warning to Americans not to travel or live there, saying the security situation in the North African country remains unstable.
There is no U.S. Embassy in Libya and "there has been evidence of hostility to the United States in some segments of the population and some elements of the Libyan government," the department said in a statement.