Prime Minister Scott Morrison condemned the video on Wednesday and called on TikTok to additional safeguards in place to ensure the removal of violent content.
“No child should be exposed to horrifying content like this and platforms like TikTok need to put in more resources to detect and tear down this sort of harmful content,” he said. “That is their responsibility.”
Australia's e-Safety Commissioner was working with TikTok to have the video removed, he said.
In a statement on Tuesday, a spokesperson for TikTok - a Chinese-owned company - said they were aware that a clip showing a suicide originally streamed on Facebook had spread to other platforms.
"We're removing content and banning accounts that repeatedly try to upload clips," they said in a statement on Twitter.
"We appreciate our community members who've reported content and warned others against watching, engaging, or sharing such videos on any platform out of respect for the individual and loved ones."
Chief executive of Australian e-safety organisation Safe on Social, Kirra Pendergast, urged parents to tell their younger children that "TikTok was broken" or confiscate their devices to minimise the risk they will see the video.
"Ban phones in the bedroom and the bathroom, that's always my number one tip," she said.
"Or, simply, pull the router out of the wall so they think the internet is broke for the next couple of days. This content is being quite widely shared so we want to minimise the damage as much as possible."
Anyone who sees the video is being encouraged to report it as "illegal and harmful content" at the eSafety Commissioner's website.
TikTok is extremely popular with children and teenagers, with an algorithm suggesting videos to users from creators they have not subscribed to.
Readers seeking support can contact Lifeline crisis support on 13 11 14, Suicide Call Back Service on 1300 659 467 and Kids Helpline on 1800 55 1800 (for young people aged 5 to 25). More information is available at Beyond Blue.org.au and lifeline.org.au. Embrace Multicultural Mental Health supports people from culturally and linguistically diverse backgrounds.