”I am grateful that President Trump and Intelligence Chief Gabbard lived up to their promise of openness”, writes King's niece Alveda King in a press release from the White House.
The documents, a total of 230,000 pages, contain details about the FBI's investigation of the murder in 1968 and the man who was convicted of having killed him, James Earl Ray.
US President Donald Trump issued a presidential decree in January to publish the documents.
The disclosure comes at the same time as the administration has been met with pressure to release investigation documents related to the convicted sex offender Jeffrey Epstein.
Previously, also classified documents linked to the murder of President John F Kennedy have been published.
