The Federal Aviation Administration (FAA) said he was piloting a small plane that wrongly crossed a runway where another aircraft was landing.
The planes were within about 3,600ft (1,100m) of each other at Los Angeles' Hawthorne airport last Friday. There was no danger of a crash, the FAA said.
Ford, 77, acknowledged his mistake and apologised, his representative said.
The representative said in a statement that the star of the Indiana Jones and Star Wars films had "misheard" an instruction from air traffic control.