Federal and state police have charged a South Australian woman with links to the Islamic State terrorism group.

Police will allege the woman cultivated a relationship with Islamic State online and pledged her allegiance.

Police said the 22-year-old woman from Adelaide's western suburbs was arrested earlier today after a search of a property.

They said the woman was an Australian citizen of African origin, having arrived in Australia at the age of 14, and gained their attention when she tried to leave the country mid-last year.

If found guilty she could face a maximum of 10 years' jail.

AFP assistant commissioner Ian McCartney said there was no threat in Australia in relation to the case.

"The charges we've laid today against this person are serious and significant and should be not underestimated," he said.

"And to reiterate, this incident is not linked to the activity that's occurred in Manchester overnight."

South Australia's assistant commissioner Linda Williams said the woman was not planning an attack.

"I would like to emphasis to the South Australian community that the accused has been charged with membership of a terrorism organisation, not with specifically planning any attack," she said.

"There is no known ongoing threat to the community."

The woman appeared in the Adelaide Magistrates Court on Tuesday afternoon.

Her lawyer Craig Caldicott told the court she would plead not guilty.

There was no application for bail and her identity has been suppressed.

Outside court, Mr Caldicott said he had not been given any statements or information about the alleged offending from the AFP.

"You would have thought by this stage after 10 months they would have a ream of material that they could place before the court," he said.

"But they are asking for several months to get their act together."