On Thursday he visited the officers who carried out his rescue and handed them the letter of thanks, according to a post on Da Nang Police news portal.
In it he wrote: "I got into an extremely bad situation and was stuck in a high waterfall. Without the rescue forces of the Da Nang City Police, I would not have been able to cope with the situation. I want to express my great gratitude to the rescue forces. You did your job very promptly and professionally."
On Sunday afternoon the 31-year-old tried to climb down the 10-meter-high waterfall that cascades off the Mo Khe Ram Stream in Hoa Vang District while experiencing adventurous activities there.
He was stuck in the middle, forcing him to cling to a rock halfway down.
After receiving information from locals, rescue forces traversed more than a kilometer of forest roads with dangerous rocky slopes.
They then used ropes and harnesses to swing across the waterfall and reach him, and slowly pulled him out.
The rescue took around 30 minutes.
Located inside a valley with pristine natural landscapes, the waterfall is in the Ba Na - Nui Chua Nature Reserve on Mount Ba Na between Da Nang and Quang Nam Province.
The area is famous for trekking and adventurous activities.