Jereth Kok was suspended in 2019 for professional misconduct in relation to the online posts that also described abortion doctors as "contract killers", equated abortion to murder and described being transgender as a mental health issue.
He is also accused of posting racist comments online about Chinese people and Islam.
The Victorian Civil and Administration Tribunal found Dr Kok engaged in professional misconduct, between May 20, 2010 and October 15, 2021, when he posted and published on social media and internet forums.
He maintains that many posts were satirical or taken out of context.
The tribunal last week upheld his ban.
It found that Dr Kok's posts were "disrespectful" and "not sufficiently balanced", despite acknowledging that many were political or religious in nature and unrelated to his clinical practice.
In one of his many posts, the general practitioner said "the Royal Women's Hospital happens to be Melbourne's premier publicly funded baby-killing facility".
The Medical Board of Australia said the comment denigrated, demeaned and slurred medical practitioners at the hospital who provided abortion treatment to patients.
While Dr Kok accepted that his commentary was "discourteous" to people who worked at the hospital, he submitted he was expressing his views and beliefs about abortion in a discussion on a Christian website.
In another comment to an online story about doctors performing abortions, Dr Kok suggested the author should replace the word doctor with "butcher".
He later told the tribunal that he would avoid this type of language in future, but said he had strong views about abortion being immoral as a Christian and believed he was required to speak out about the issue.
He also referred to treatment of gender dysphoria as "medical butchery".
Other posts were found to have denigrated, demeaned and slurred medical practitioners who recognise and treat gender dysphoria, perform abortion treatment and those who followed COVID-19 public health orders.
He was also found to have expressed sentiments of violence and made derogatory statements towards racial and religious groups, LGBTQI+ people and legitimised anti-vaccination during the COVID pandemic.
Political party Family First on Monday slammed the decision - calling it a "gross injustice and chilling attack on freedom of speech".
Family First's national director Lyle Shelton said the party will fight to repeal similar anti-free speech laws in all states starting with fielding candidates at upcoming elections in South Australia, Victoria and NSW.
"Dr Kok has harmed no patient. His only 'crime' was to express his views online — many of them satirical or Christian in nature — and for that, he has been punished with the loss of his medical career," Mr Shelton said.
"We will not sit by while the state tramples conscience, truth and freedom.
"Dr Kok's case must be the turning point."
The matter is expected to return to the tribunal for an administrative mention in September.
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