The 27-year-old Chen won in straight sets 21-18, 21-18 to claim hisfirst Olympic gold after taking bronze in the London 2012 Games andwinning the world title in both 2014 and 2015.
Lee is number one in the world but had lost two consecutive finals toChinese great Lin Dan. Lee finally defeated Lin in the Rio semi-finalbut at 33, may now end his career without an Olympic gold havingfallen short against Chen.
China have been a powerhouse in Olympic badminton in recent years butRio has seen their dominance eroded. They only claimed their firstgold on Friday in the men's doubles and Chen paid credit tocompatriots Zhang Nan and Fu Haifeng for inspiring him.
"Yesterday the men's doubles won the first (badminton) gold for theChinese team in this Olympic Games, so it was a huge encouragementfor me to channel that confidence and put it into today's match," hesaid.
"Me winning today has everything to do with my team-mates' goodresult yesterday."
Earlier Saturday, the two-time reigning Olympic champion Lin endedthe Rio Games without a medal by losing the bronze clash withDenmark's Viktor Axelsen.
China's Lin has dominated the sport with five world titles inaddition to Olympic golds from 2008 and 2012 but Axelsen shocked thefavourite 2-1 (15-21, 21-10, 21-17) for a medal on his first trip tothe Games.
"It is hard to describe how this feels," the Dane said. "It is thefeeling of winning and everything working for you when you haveworked so hard for a long time. It's just one of the best feelings inthe world for sure."
Lin admitted he felt tired going into the decisive third set havinglost to Lee in a marathon semi-final the day before.
"Today we also entered the third set," he said. "It is a pretty hugechallenge for me in terms of stamina because yesterday I foughtreally hard.
Lin is a little younger than Lee at 32 but said he would now have toconsider whether to attempt to compete at Tokyo 2020.
"I did not think about it much, because I was focusing myself fullyon this Olympic Games," he said. "After this one, I will rest for awhile and then go from there."