A petition calling for an investigation into the "standard of food served to the military and Sodexo services" has attracted more than 15,000 signatures.
The petition, which was set up by Claire Wingate on the official UK Parliament website, states: "I have witnessed the standard of food served to the military. Sodexo provides unhealthy food cold and substandard services.
"Government spend less per head on a soldier than it does on a prisoner (sic)."
It is "shameful to do this to the military personnel," the petition states.
It also claims that complaints have been ignored and that the meals would not be suitable to be served in schools.
People have been taking to social media to post pictures of meals allegedly served in military bases. Some show maggot-infested tomatoes, raw chicken and mouldy eggs. However, it is not clear where the photos have been taken nor whether they actually come from sites served by Sodexo.
One posted an open letter to the army on social media, complaining about food allegedly served by Sodexo.
He wrote: "Would you feed a homeless person undercooked or raw chicken? Would you serve it to a paying customer in a restaurant? Would you feed it to your kids for their dinner?
"I would like to think the answer to these questions is, no of course not. So why is the answer yes to serving soldiers paying for these meals?"
A spokesperson for Sodexo said: "We are one of a number of companies who provide catering services to the armed forces and we take very seriously any complaints about the quality of our food."
"We are aware of the petition and are keen to investigate complaints properly but can only do so if customers inform the Sodexo team, where they purchase the food at the time, so that the issue can be looked into straight away."
Sodexo supplies more than 80 army, navy and RAF sites in the UK, Cyprus and the Falkland Islands.
The deadline for the petition is 21 July but the government will have to respond to it as it has already reached more than 10,000 signatures.