Weeks after being attacked with boiling water, Daniel Morcombe's killer Brett Peter Cowan has been allowed to use a different name in prison.

Cowan legally changed his name to Shaddo N-unyah Hunter in 2013 and has now been given approval to use the name in prison, News Corp reports.

Cowan told detectives investigating the Morcombe murder he had chosen Shaddo because it was his dog's name, while N-unyah stood for "none of your business", a News Corp newspaper reports.

A Queensland Corrective Services spokesman was unable to comment on individual cases but told AAP prisoners born outside Queensland are legally entitled to be addressed under their new identity.