The programme works by giving a convincing impression of a young person taking part in a chatroom conversation, while at the same time analysing the behaviour of the person it is chatting with.
Internet chatrooms are seen as areas where youngsters are at most risk of "grooming" - the term used to describe a paedophile building up a rapport with a victim.
The ChatNannies programme was developed by IT consultant Jim Whightman, the New Scientist magazine reported on Wednesday.
It creates thousands of sub-programs, called nanniebots, which log on to different chatrooms and strike up conversations with users and user groups.
If the program detects any suspicious activity, it emails a transcript of the conversation to Whightman, who then decides if the police should be contacted.
"If this software works, then it would be marvellous because there is nothing like this out there," said Chris Atkinson, internet safety officer with the National Society for the Prevention of Cruelty to Children in the UK.
Whightman said he currently has 100,000 nanniebots circulating around chatrooms.