Mark Latham has announced he will join the Liberal Democrats headed by David Leyonhjelm and launched an attack on his former party, saying Labor "can go and get stuffed".
The former Labor leader announced the move in a post on his Facebook page, saying he wants to "play a role in fighting for our national values".
"I support 80-90 per cent of the Liberal Democrats platform, pretty good for someone with strong views formed over a long period of time," Mr Latham wrote.
"Plus, as a party of freedom, the Liberal Democrats allow room for dissent and diversity of opinion.
"So I have joined up and want to play a role in fighting for our national values, based on personal freedom and responsibility."
Mr Latham also took a swipe at his former party, saying Labor had barred him from speaking at membership events in western Sydney.
He added that the Labor Party under the leadership of Bill Shorten is "only interested in diversity of skin colour, gender and sexuality".
Watch: Labor's 'shocker' Australia First ad
Speaking to Sky News' Andrew Bolt in the wake of his announcement, Mr Latham said the Labor Party "can go and get stuffed".
"I am going to speak and people can process my information – they'll tell me when I'm wrong. The Australian people are pretty smart," he said.
He added that moves to curtail freedom of speech in Australia are symptomatic of a "struggle to save our Western civilisation".
Asked about the possibility of seeking election to parliament for the Liberal Democrats in the future, he said: "I'm up for the fight to save our civilisation. I'm against anybody who wants to roll back the principles of meritocracy.
"I'm available to fight the good battle in any forum at any time ... If the time comes where I thought that the best way to muster that fight is in one of the parliaments of the country, then I'd do that."
Mr Latham led Labor to defeat against former Liberal Prime Minister John Howard in the 2004 federal election.
He was sacked as a contributor to Sky News in March following a series of controversial remarks, including his suggestion that a high school student was "gay" because he took part in a video supporting feminism.
Sky News presenter and former NSW Premier Kristina Keneally also made a formal complaint against Mr Latham, alleging that an on-air attack he made was defamatory.
Mr Latham's announcement comes on the same day the Labor Party was attacked for a new advertisement championing an 'Australians First' approach, which critics say was "extremely xenophobic".
