The infant was listed on the payment slip of a local council in Zamfara State in northern Nigeria, the Nigerian Daily Times reported.
Adding family members to the payroll is a common practice among local government officials, according to state justice commissioner Garba Gajam.
This latest fraud was discovered during an investigation into such "ghost workers", he said.
Whoever put the baby on the payroll made sure to give it an attractive resume, Gajam told Agence France Presse:
"What is even more astonishing is that it was indicated in the payroll that the infant holds an ordinary national diploma."
The culprit will be made to return the baby's wages and face charges of misappropriating public funds.
Investigators were alerted to the practice when the name of a five-month-old baby was found another local municipality's payroll in August, said Gajam:
"We have been receiving amazing revelations which point to the rot and abysmal level of corruption at the local government level."
Human Rights Watch describes government corruption in Nigeria as "endemic".