South Australia's Attorney-General says he doubts new classification rules for video games are being applied rigorously and will write to the Federal Government seeking scrutiny of the board involved.

John Rau said the new system might be exposing children to sexual or violent content.

He said the South Australian Government had backed introduction of an R18+ classification and tightened MA15+ rules.

But Mr Rau questioned the application of the rules since their introduction last January.

He said more than a dozen video games released this year had been given a MA15+ rating in Australia but higher age classifications in European countries and the United States.

"It is concerning to me, particularly as a parent, when I see that 13 games have been released in Australia as MA15+ whilst exactly the same game attracts up to an R18+ classification overseas," he said.

"These particular games have been assessed as having intense violence, blood and gore, nudity and suggestive themes."

The games include Killer is Dead, Alien Rage, God Mode and the Walking Dead.

Mr Rau said he wanted the new federal Attorney-General George Brandis to review the way the Australian Classification Board was assessing new video games.

"If the standards are not more rigorously applied I will be referring each of these games to the South Australian Classification Council for review," he said.

He said the Australian Council on Children and the Media has approached him with concerns.

Mr Rau was satisfied with the game, Grand Theft Auto V, having been given an R18+ classification before its release this week.

Games trader Robert Jenkins said those making classification rulings had a tough job.

"This is the difficult job that the office has in Canberra is that these games can go 10, 20, 30 hours of game play and who can possibly sit there and play every single video game that comes out just to see in case there's something there?" he said.

New federal Justice Minister Michael Keenan said the national classification scheme worked effectively and South Australia could go it alone if it wanted.

Mr Rau responded: "I will if I have to, but I would prefer to see if we could do this as a uniform national approach."