The man told rescuers he was fishing when he was hit by several large waves.
"I managed to hold on as the first wave hit me on the chest, but I was overwhelmed by the second and bigger wave," he said.
That began an odyssey covering 60 hours surviving at sea despite the fact he can’t swim.
Tseng Lien-fa told Sky News he grabbed the coffin lid thinking it was just a piece of floating wood junk.
But this time the coffin led, normally a part of death, kept the fisherman alive. Tseng floated on the lid until he floated near a beach.
He told Reuters through the BBC "when my feet touched sand, I relaxed and was pushed by the waves onto shore."
Tseng was in remarkably good physical condition despite going without food or water for two days. He had sores caused by the salt water and was somewhat dehydrated but otherwise, just fine.
"Considering the fact that he had not taken in any food or water while drifting at sea for 60 hours and he remained conscious, all I could say about him was that this was a miracle," a doctor in Taiwan reported.
Tseng is engaged with a baby on the way next month. He has promised his fiance' his fishing days are over.