The fire service also criticized another popular cartoon character, Fireman Sam.
Predictably, the LFB's tweets have sparked a massive debate online, with one user firing back by posting a picture from a Peppa Pig book which features several women firefighters.
Even TV presenter Piers Morgan waded in to the fray, tweeting: "If women are being 'put off' joining the fire service because Fireman Sam - A CARTOON CHARACTER - supposedly 'perpetuates male stereotypes' then can I politely suggest these women probably don't have what it takes to fight fires."
Another Twitter user pointed out that Fireman Sam features a woman called Firefighter Penny Morris, but the LFB insisted her presence is "completely devalued" by the show's name.
The LFB says it currently employs 354 female firefighters - 7.39 percent of its operational workforce.
Speaking to CNN, a spokesperson for the LFB said: "We need to challenge outdated language that our research is showing is stopping young girls and women from considering firefighting as a rewarding and professional career.
"It was widely reported that a four-year-old named Esme came home and said she couldn't be a firefighter because she was a girl. This shows that children's cartoons make a huge impression on young people and it's time for all media to treat us with respect and call us firefighters what we have been for the past 30 years."
Mattel, which produces Fireman Sam also told CNN that "We have enormous respect for all firefighters and the work that they do; we are committed to representing their work in the most appropriate way through our entertaining show for children.
"Fireman Sam is a much loved and iconic brand and we are constantly evolving to make sure that we stay true to the show's heritage as well as representing the world that children see around them today.
"The team are always referred to throughout the show as 'firefighters' except Sam who has not evolved his title in his role as the show's namesake.
"We recognise the need to stay relevant and we continue to evaluate the show to ensure Sam remains an aspirational hero for generations of preschoolers."
