A broad alliance of charities and human rights groups say proposed new rules are an attack on democracy and will impact on their work with the vulnerable.
The proposed regulations would give the charities commissioner extraordinary powers to deregister a charity linked to illegal activity.
"We may see, for merely putting a sticker on a lamp post, the removal of charitable status from some of our most important and established organisations," Australian Council for Social Service spokeswoman Emma Campbell said outside parliament on Tuesday.
The federal minister responsible, Michael Sukkar, says the new regulations are intended to strip tax concessions and other benefits from charities that misrepresent their status for illegal gain or are involved in criminal activity.
Chief executive of the Alliance for Gambling Reform Gordon Ramsay, said the regulations are misdirected, poorly drafted, and don't serve the public or the most vulnerable.
A vigil for a death or blocking a footpath at a protest could prompt action.
"Who they'll come after first is anyone's guess," Anglicare Australia boss Kasy Chambers said.
"They are not just an attack on charities. They are an attack on democracy."
Groups opposed include Vinnies, Baptist Care, Save the Children, Oxfam, Amnesty, Fred Hollows Foundation, Caritas Australia, WWF-Australia, ACOSS, People with Disability Australia, Public Health Association of Australia, Catholic Social Services Australia, and the Foundation for Alcohol Research and Education.
The not-for-profit organisations warn their time and donations will be tied up in unprecedented red tape and legal fees, depriving communities of vital support.
Some government members have also called for changes to the regulations, as current laws already target shonky charities and employers.
