Mr Trump said it was a "special night for these really great people" as they arrived at the Andrews Air Force Base near Washington.
The White House said the trio had been freed as a gesture of goodwill ahead of the planned meeting between Mr Trump and North Korean leader Kim Jong-un.
Mr Trump said he thought the summit would be "a big success".
TVNL Comment: Uh...for the record...two of the three released men were imprisoned on Trump's watch.