Pc David Crawford took to Facebook to mock the women, calling them "tramps" and accusing them of being cheap and common.
He finished his rant with the words: "Ladies Day - more like Halloween".
Ladies' Day at the Liverpool course, held two days before the Grand National, is the most high-profile event of its kind in British horse racing and a highlight of the British fashion calendar.
Thousands flocked from across the country for this year's 53,000-strong sell-out, including Coleen Rooney, wife of the Manchester United footballer Wayne Rooney, and the model Danielle Lloyd, despite the high winds and heavy rain.
Yet the day clearly did not go down with Pc Crawford. He wrote: "Enjoy 'ladies' day - ladies" before accusing them of being "back to drinkLambrini at 10 in the morning watching Jeremy Kyle whilst shouting the kids 'Britney and Tyson come down for ya pork scratching breakfast'."
He went on to comment on the use of "ten quid fake bake tan....smeared all over the place" and ended with: "Tramps! Ladies Day - more like Halloween! Rant over."
He went on in response to a comment back at him to say it "does me head in".
Whilst his comments may have been appreciated as a bit of a joke by some of his friends on Facebook, Merseyside police have taken a stronger view and have referred complaints of the outburst to the force's standards department.
A spokesperson from the force said: "We have been made aware of some comments made on a social networking site by a person who may be a serving police officer about an event.
"The matter has been referred to the Force's Police Standards Department.
"As a result it would be inappropriate to comment any further."
Pc Crawford's Facebook page has now been removed.
His views, unsurprisingly, did not go down well with Liverpool women.
Justine Mills, the managing director of Cricket, a Liverpool-based designer boutique whose clients include Mrs Rooney and Alex Curran, Liverpool midfielder Steven Gerrard's wife, said: "It is a fantastic occasion but unfortunately a lot of attention is focused on a minority who attend Ladies Day and the Grand National.
"We all have a voyeuristic desire to see fashion mishaps but they are the few in amongst thousands of people who go to Aintree.
"The majority of people who are clients of Cricket comment on how remarkable Liverpool women look at the races."
Joanne Sloan, 39, from Southport, who attended Ladies' Day, said she went to prove that Merseyside girls are not all "trashy" dressers.
She said: "We have got a bad reputation when it comes to dress sense but I think we can do it all; vintage, classy and glamour."
Earlier this year Essex police revealed that up to a dozen police officers were under investigation over comments made on Facebook.
Their remarks include comments about wanting to beat up rioting students and describing a suspected paedophile who flashed at children in a play area as 'a dirty scum pervert'.
Another officer posted a video on the social networking site of a U.S. policeman flooring a suspect by shoving him in the neck, writing: "How cool is the copper!"