Scores of passengers were taken in by a post on a Facebook account titled "First Buses" - and which used the firm's logo which claimed that from September 1, all prams and pushchairs would be banned on all services.
The post was shared nearly 13,000 times - with many falling for the hoax.
But the account has now been deleted after bosses at the genuine First Bus company complained to Facebook.
A spokesman said: "After becoming aware of the fake Facebook page we have contacted Facebook and this page has been removed.
"We would like to thank staff and customers for bringing this to our attention. Details for official First Bus social media accounts can be found through our website."
The post was shared by thousands of people and read: "First, the 'buggy spaces' are actually primarily for wheelchair users.
"Secondly, normal passengers complain in their droves daily about having their journeys spoiled by Lonsdale clad "full time yummy mummies" and their semi human offspring, who are often left to sit in the pushchair scoffing Quavers whilst staring unnervingly with their bozz eyes, all while mummy sits on Snapchat, "hilariously" adding dog ears to her latest selfie.
"However, we are not cruel for the sake of it. Buggies and prams will still be allowed, provided they are folded up, meaning that mummy will need to pay attention to little Alfie when they "go to visit Auntie Louise", who is not an actual aunt but just a scratter friend of mummy. We trust these measures meet with the approval of our loyal patrons.
"Thank You - The First Buses Team."
While many saw through the joke, others were taken in.
One wrote: "What a service u provide ? Well after your statements I'd rather walk than catch a bus."
Another wrote: "I think this is absolutely disgraceful you people at first busses (sic) should be discussed (sic) with yourself."
Another post added: "That's ok for a parent with one child how does someone with twins supposed to hold two children and fold up a double buggy. Is the driver going to help? I don't think so."