The 24-year-old was taken into custody on Friday after search warrants were executed in Chester Hill and Sefton.
He has been charged with membership of a terrorist organisation, Australian Federal Police and NSW Police said on Saturday.
They will allege the man’s online rhetoric was escalating and that he had collected a large amount of extremist material.
He’s also accused of possessing several improvised explosive recipes and pledging allegiance to Islamic State.
The NSW Joint Counter Terrorism Team investigated the man for seven months.
AFP commander Stephen Dametto said the man’s conduct doesn’t represent the Islamic faith.
“His actions are criminal and they represent hatred and terror,” he said.
“It shows there are still those in the community that seek to do us harm.”
Commander Dametto said IS remains a threat and continues to radicalise people in Australia.
The man is expected to face Parramatta Local Court on Saturday.