One particularly gruesome creation had Mrs May laying back on a hospital bed clad in a Union flag dress.
She is shown gazing with love at a deformed “Brexit” baby attached to her by an umbilical cord.
A further float shows Mrs May with a baby on her shoulder.
The floats delighted the German crowds and some Remainers were quick to join in the mockery on social media.
One Tweeter Brexit Bin, tweeted: “A deluded May has given birth to a pathetic, over optimistic, idiotic abomination.
“That’s what the German carnival season thinks of Brexit.”
Another chimed in: “We are the laughing stock of Europe.”
But even some of those who do not support Brexit thought the floats were too much.
One wrote: “I am opposed to Brexit but this is going too far. German humour is zero and stupid.”
Another said: “I do not support Brexit but I think this is being cruel.”
Last year, the carnival featured another float of Mrs May, this time with a gun bearing the word “brevet” inserted into her mouth.
The British PM was not the only world leader to be brutally satirised at this year’s event.
One float showed Donald Trump being mounted by a Russian bear while another represented him and Kim Jong-un as babies with nuclear missile toys.
German Chancellor Angela Merkel was depicted as a grotesque spider while Martin Schulz was shown putting himself into a mincer.
And French leader Emmanuel Macron became Napoleon, poking out of the top of a wrecked car with an EU flag on the side.
The parades are held on the Monday before Ash Wednesday and are celebrated across the German speaking world.
They are particularly popular in the Rhineland where the floats are known to cause controversy.