The registered charity said deathcap mushrooms are starting to appear in southern and western regions of Australia.
Australian authorities advise consumers to only eat mushrooms purchased from the supermarket, greengrocer or reputable source.
The Marbled Death Cap mushroom has been found growing wild in Denmark.
Four people have died after eating deathcap mushrooms in the Australian Capital Territory in the past 16 years, said the council.
Two people died after eating them in 2012 at a New Year's Eve dinner party in Canberra and in 2014 four people were seriously poisoned, it added.
The mushrooms start to appear at this time of year and have been found in Canberra, in and around Melbourne and in Adelaide.
They are not native to Australia and are often found near oak trees growing in warm wet weather during autumn.
Rachelle Williams, Council chair, said there is enough poison in one deathcap mushroom to kill a healthy adult.
“The similar marbled deathcap mushrooms have also been recently found in Western Australia. While no cases have been reported in New South Wales or Tasmania it may be possible that they grow there,” she said.
“Deathcap mushrooms are difficult to distinguish from other wild mushrooms so we recommend you play it safe and only eat mushrooms that you have purchased from the supermarket, greengrocer or other reputable source.
“People born overseas, especially in Asian countries, should be aware that these deadly mushrooms can look like edible mushrooms that they may have gathered overseas.”
Toxin in deathcap mushrooms is not destroyed by cooking.
Symptoms include vomiting, diarrhoea and stomach cramps and often don’t appear until 10 to 16 hours after eating.
Without effective medical intervention people may go into a coma and die after two or three weeks of liver and kidney failure.
Nine out of ten cases of mushroom poisoning result from the deathcap variety, said Williams.
“However there are other wild mushrooms in Australia that, while not fatal, can make you ill with vomiting and diarrhoea. These include the yellow stainer which resembles a field mushroom and is the most commonly ingested poisonous mushroom in Victoria.
“Many reported cases of fungi poisoning are in children under five years of age. Most young children who eat poisonous mushrooms find them in the garden at home. Children younger than five years of age have a natural inclination to put things in their mouths.”
The French Agency for Food, Environmental and Occupational Food and Safety (ANSES) and the Directorate General for Health (DGS) compiled recommendations for wild mushroom gatherers after close to 100 people were poisoned late last year.
From June to August 2015 the Institut national de veille sanitaire (InVS) reported 212 poisonings due to eating wild mushrooms.