Online users posted a purported clip from the Bedaya TV programme which appeared to show men dancing. One stood closely behind another, held the man's hips, and seemed to mimic a sexual act.
Social media users created an online storm over the scene from the show called "Increase Your Credit".
With the hashtag "Pornographic scene on Bedaya channel", they called for punishment of the "molester" and for the closure of the channel which was founded in 2005.
"A dirty scene and broadcast on a highly viewed channel," wrote Twitter user @mkhawe15.
"The Ministry of Information must immediately stop the channel".
A post from @FarraJIK called it "a dirty channel," while @alamih42 said Bedaya had presented itself as an Islamic station "yet insults religion."
Bedaya took to Twitter to apologise, saying mistakes can happen during live broadcasting.
"The act that took place by one of our contestants, an act which is not accepted by any logic, any religion, or moral values, was apologised for by the contestant," the channel stated.
"The act was unintended by him, and he has repented to God".
Bedaya added that the contestant has been disqualified and his act does "not represent the channel or its goals to spread values and morals".
It said the "Increase Your Credit" show aims to promote a culture of earning and saving, while preparing youth for the labour market.
On Wednesday afternoon Bedaya TV showed a live Koran reading from a mosque, and then a food show.
Saudi Arabia is founded on ultra-conservative Wahhabi thought and forbids mixing of the sexes in many public places.
But more than half of the kingdom's citizens are under the age of 25. There are pressures for social change despite the kingdom's strict foundations.
