The dance-music channel, MTV Base, will be forced to broadcast on on-air apology after transmitting the controversial video for the Prodigy's Smack My Bitch Up before the watershed.
MTV has been ordered to air the apology by the independent television commission after seven viewers complained the video was unsuitable for broadcast at 6.40pm.
The ITC said it considered the incident, which occurred on September 5, a "serious breach" of its programme code.
The six-year-old video was hugely controversial when first released and shows scenes of drug taking, vomiting and sex.
MTV agreed the video should not have been shown at 6.40pm and apologised for any offence caused.
MTV said it had mistaken Smack My Bitch Up - which is marked as only suitable for transmission between 1am and 4am - for another video.
The apology will be broadcast on Wednesday December 12 between 6.30pm and 7pm.