The authority received a Freedom of Information request which said provisions to deal with an attack, often seen in horror films, were poor.
The "concerned citizen" said the possibility of such an event was one that councils should be aware of.
"We've had a few wacky ones before but this one did make us laugh," said Lynn Wyeth, head of information governance.
The Freedom of Information Act allows a right of access to recorded information held by public authorities.
Ms Wyeth said she was unaware of any specific reference to a zombie attack in the council's emergency plan, however some elements of it could be applied if the situation arose.
Other submissions to the council have included requests for records of paranormal activity and haunted buildings within the city.
"To you it might seem frivolous and a waste of time... but to different people it actually means something," said Ms Wyeth.
"Everybody has their own interests and their own reasons for asking these questions."
She added high-profile cases, such as the MPs expenses scandal, has raised public awareness of the right to request information records.
Ed Thurlow, who runs zombie website Terror4Fun, said he felt a zombie invasion in Leicester was highly unlikely.
"I think perhaps [the "Concerned Citizen"] has watched films like 28 Days Later a few too many times.