A number of laptops were stolen in the burglary
An investigation is under way after a computer containing the details of 33,000 children was stolen.
Burglars stole the laptop from offices of Wigan Borough Council in January, but authority chiefs have only just disclosed the incident.
The details included names, dates of birth, and any special needs and free meal eligibility of children aged between seven and 16.
Officials are writing to the parents and carers of those affected.
The information is password protected and bosses believe that the information will be of little use to those who stole the computer.
Director of Children and Young People's Services, Nick Hudson, said: "Apart from the names, the data on the children is in the form of numbers and codes and there are no comments or individual case notes.
"We have taken the step of informing the public of the borough about the theft because we believe people deserve to know what has happened.
Police in Wigan have been informed and are investigating the break-in on 27 January. The laptop was one of a number of computers stolen.
Mr Hudson said the information would be of no use to the thieves and may have been deleted.
"However we are investigating this incident thoroughly and we are working very hard to learn the lessons and to ensure that our children's privacy is protected as well as possible in the future," he added.
Council bosses have reported the data theft to the office of the Information Commissioner.