Pope Francis appeared for a few minutes on a balcony of the Gemelli Hospital in Rome on Sunday, smiling but looking frail.
He waved with both hands but appeared to be unable to raise his arms.
''Thank you everyone," he told a crowd of about 1,000 as he made the sign of the cross with one of his hands.
The Pope has been in hospital for 38 days but is due to return to the Vatican later on Sunday.
He has suffered double pneumonia but did not use breathing equipment during his appearance.