The controversial columnist, who is a staunch Leave campaigner, tweeted videos and images from the march claiming “the little people didn’t know what they voted for”.
Another scathing tweet simply read: “Dear God.”
The comments sparked outrage as hundreds of thousands of campaigners descended on central London for the People’s Vote March two years on from the Brexit referendum.
One person replied to Ms Hopkins’ tweet and wrote: “Why do you hate humanity so, Katie Hopkins? What is it that impels you to take some kind of twisted revenge on normal people?”
Another added: “Honestly you make me laugh @KTHopkins. If the vote had gone the other way do honestly think there wouldn’t have been calls for another vote by the brexiteers? Of course there would. If people feel strongly about an issue they will fight for it - and they have every right to do so.”
One man said: “We are not enemies .. Unless you take the role of an aggressor .. You really are disturbed.. I pity you.”
Another branded Ms Hopkins “pathetic”.
Others backed the TV personality saying Remain campaigners “need to get over it”.
One supporter said: “When will people realise democracy has spoken. We don’t replay footie matches until we get what we want.”
That's a heck of a lot of "enemies" love... Are you sure you've got this?— Perdida 🇬🇧🇪🇸🇪🇺 (@maria_hoskins) June 23, 2018
Demonstrators marched to voice their “anger and frustration at the way politicians have made a mess of Brexit,” a spokesman said.
Lib Dem leader Sir Vince Cable, Green co-leader Caroline Lucas, Labour former NEC member and actor Tony Robinson and pro-EU campaigner Gina Miller were among those who joined the crowd in the capital on the second anniversary of the EU vote.
World War Two veteran Stephen Goodall, 96, led the pro-EU protesters as they headed from Pall Mall to Parliament Square.
There were boos from the crowd as the march approached Downing Street. After showing anger towards the PM, some began to chant "where's Jeremy Corbyn?"
The UK voted to leave the EU by a margin of 51.9 per cent to 48.1 per cent in a referendum held on 23 June 2016.
Britain is due to leave on 29 March 2019.