Hopkins wrote in Trump's defence for saying the US should bar Muslims from entering the country, a stance that has otherwise brought him near-universal condemnation.
Trump also claimed parts of London were so "radicalised" it left the police scared to enter them, triggering a spat with Boris Johnson, who said Trump was "out of his mind".
Hopkins wrote that she and Trump had a lot in common, saying: "I hear cries that he is a blithering idiot. I have often been called a deranged fool. But if this were true you could ignore me, ignore us, imaging the two of us shouting naked at the rain.
"It's because we articulate sentiments repressed by the politically correct consensus that we have a voice."
A petition calling for Trump to be banned from entering the UK over his comments has attracted more than 400,000 signatures.
Trump praised Hopkins and said Britain was 'trying hard to disguise their massive Muslim problem".
The United Kingdom is trying hard to disguise their massive Muslim problem. Everybody is wise to what is happening, very sad! Be honest.— Donald J. Trump (@realDonaldTrump) December 10, 2015
In response to Trump's praise, Hopkins tweeted to the presidential candidate that he had "a lot of support in the UK" and that the "liberal left love a petition," sharing another one calling for her to be sacked as a columnist.
She then tweeted: "Feeling uptight? Go click on another petition. See if it makes you feel powerful. Fools."
Feeling uptight? Go click on another petition. See if it makes you feel powerful. Fools. https://t.co/5SaKwd02Hu— Katie Hopkins (@KTHopkins) December 10, 2015
Unfortunately for MailOnline, Trump's tweet directed people to Mail.com, a completely different website.
Trump also praised Hopkins' appearance on Fox News on Thursday morning, in which she said a quarter of Britons backed his position.
A YouGov poll published today found 25% of Britons thought Trump's idea was "appropriate".
On Fox And Friends, Hopkins described life in Britain as she saw it.
She said: "We've seen our people jump out to say 'well, absolutely there is no Islamophobia here in the UK, you can walk anywhere. Everywhere's free and open. We're so multicultural. We love it.'
"The truth is very different in the UK. There are places where people like me wouldn't want to walk. Places in the UK that feel like they've completely transformed into Muslim-only areas and we have had groups patrolling the streets to say 'this is a Muslim area, keep out.'"