He Liesheng says he was only trying to train his son to be strong and manly, but the footage has ignited debate about the tough parenting style for which China became known after Amy Chua's book Battle Hymn of the Tiger Mother.
"He agreed to go out to run in the snow naked or else it wouldn't be possible for me to take his clothes off," said He, who runs a bed linen company in the eastern city of Nanjing.
"He wasn't very happy when he felt the cold."
It is not clear who posted the video online. He's personal assistant, a woman called Xin Lijuan, said He had sent the video to "a few friends" but didn't post it online himself.
The father has been given the nickname "Eagle Dad" in reference to Chua, who sparked controversy when she wrote a book extolling the benefits of tough parenting.
He, who also claims to teach his son Kung Fu, dancing, cycling and mountain climbing, said he was trying to help his child develop a "masculine temperament".
"I also give him cold ice cream on cold winter days to train his stomach to get used to the cold," He said by phone.
"He rarely has a cold or fever."
Xin said He was on holiday with his family in New York during the Lunar New Year holiday last month and decided to see in the Year of the Dragon with this unusual method.
"The child agreed and before the run, he did half an hour of slow running to warm up," she said by phone.
"This child has received all sorts of forms of training since he was small. When he was one, he started swimming in water that was 21°."
Thousands of views
Xin said that the boy was born prematurely with several health problems including water in the brain that prompted doctors to say he may have cerebral palsy.
"But now he has no problems," she said, attributing this to He's intense education method.
In the video, the little boy runs towards his father, who is filming him, in thick snow with only his shoes and underpants on, at times crying and pleading with his dad to take him in his arms.
On several occasions, both parents tell their son to lie down in the snow, which he does eventually when his mother presses him.
The footage has been viewed by tens of thousands of people on video-sharing websites.
"I don't agree with this... We should give children a happy childhood, those terrible parents say they do this for their child's own good, but I think their purpose is just to be able to brag in the future," one netizen said.
The Chinese way
"I really don't support this, poor kid. Does the kid's mother let the father do whatever he wants to do?" another person said on Sina's popular weibo microblogging service.
Chinese parenting has come under the spotlight recently, with many of the country's children forced to study harder than their Western counterparts, often at the expense of sports and other leisure activities.
In her controversial book Battle Hymn of the Tiger Mother, Chinese-American Chua, a Yale University law professor, tells how she and her husband elected to raise their two daughters the "Chinese" way.
That meant heavy pressure for top school marks, no sleep-overs or watching television and mandatory piano or violin study.
In one incident, she made one of her daughters stand out in the cold for falling short on piano practice, while in another she tells guests at a dinner party how she once called her daughter "garbage" - shocking the room.
An excerpt from the book was published in the Wall Street Journal last year, sparking vicious criticism and, Chua says, death threats.
Most of the responses to He's parenting methods were critical, although some internet posts said teaching one's child about the cold and fortitude was a good thing.
"But if this method becomes a feature of everyday life, then the child's life learning process is just cruel," one person said.
Another blogger said: "His father is cruel, but what he did is for the boy's good. He won't be like today's children, who are only able to play with cell phones and computers."
Xin said He had disregarded the flood of online criticism.
"He says he doesn't care what others say... that the fact that the child lived showed that he has tenacious vitality," she said.