The legendary boxing promoter was at Madison Square Garden on Saturday evening to host the showdown between Roy Jones Jr and Felix 'Tito' Trinidad.
On the same night, UFC80: Rapid Fire in the UK was also attracting a large chunk of the US pay-per-view audience.
Asked for his opinion of MMA, King said: "I think it's great. I think mixed martial arts is original."
But King went on to explain: "It's barbarism."
With a trademark flurry of words, the 76-year-old who has enjoyed four decades at the top of the fight game, claimed that MMA is a step backwards compared to the "beauty" of present day boxing.
King said: "This is what the Marquess of Queensberry came to uplift by making rules and regulations.
"It won't be long before they'll be crying barbarism again.
"If people are thinking quality is blood and guts, that they want to go out and see guys get knocked out of the building...
"Well, in the olden days they were feeding Christians to the lions. Then they had the gladiators.
"Later, you had fighters who would go 50 rounds, there was no such thing as going to a decision, you were going for a knockout.
"So then people became more civilised, more sophisticated, and that's how you got the beauty that is boxing."
Asked what he would say to those who claim boxing has lost its competitive edge and is not as popular as it once was, he smiled: "Well I say to them, 'Oh ye of little faith. Get thee behind me Satan!
"You've got to understand something. Boxing, right now, is an equal opportunity sport. Especially now as you have no heroes.
"Why do I say that? I say that because anybody can be the champion. We don't even know who the champion is, we don't have heroes right now.
"And why don't we have heroes? Because our fighters became business boxers, rather than boxers of business. They all became the businessmen they wanted to be without fighting for glory and pride.
"Pride will prevail. When it's all over, you can try to hide it, you can be like an ostrich and bury your head in the sand.
"But when a person competes for the pride, integrity and honour of his competition, it is incidental that he should be paid.
"You don't have to trade in one for the other. You don't have to show greed and avarice and mercenary qualities in order to be good.
"Be good and you're gonna have the money."
Don King was speaking at the unveiling of his new video game "Don King Presents: Prizefighter".
The title will be available in spring on Xbox 360, Nintendo Wii and DS. For more information, log on to the 2Ksports website.