The incident happened off the coast of Hawaii, which was the pilot's destination flying solo from Monterey.
The Coast Guard said the pilot called for help about 400 miles east of Hilo after noticing his plane was low on fuel. The guard sent a plane to fly alongside the Cessna.
Crew members coached the man through a crash landing in choppy seas 13 miles off the coastline.
A helicopter quickly plucked the 65-year-old pilot from the ocean. Rescuers said he was very calm.
"He was very professional throughout the whole scenario, but I know I probably would have been a little more freaked out," said U.S. Coast Guard Ryan Rejzer.
The pilot was taken to the hospital. There was no word on his condition, but authorities said he did not appear to have any significant injuries.