Kristy Howard is warning other parents after her kids' Playstation 3 came with porn saved on the hard drive. Kevin Farmer

MOTHER-of-three Kristy Howard knew to check on her kids when the usually rambunctious youngsters were suddenly quiet in the lounge room.

She was shocked to see her three children staring at the first scenes of a pornographic movie playing on a television screen.

"We walked in as they clicked it on," Mrs Howard said.

The source of the lewd movie was a video game console which she and her husband had bought at a pawn shop at Wilsonton on December 19 to keep her children entertained over the school holiday break.

"I said 'shut your eyes'."

Her children had been satisfied playing the game that came with the system for a few days before they started exploring the hard drive of the Playstation 3.

"They (children) went into the video part of it and there were over 10 porn movies there."

She said the download dates on the blue movies showed they had been accessed before her family bought the machine.

The pawn shop's owner Joe Mathers said he wouldn't have sold the console had he known the nature of the content stored on it.

He said it was a challenge to keep up with advances in gaming console technology.

"I just have to be a bit more diligent in learning how to check these hard drives," Mr Mathers said.

Mrs Howard wanted to warn other parents about the possibility of unwanted content on second-hand hard drives.