NSW will ban all zombie knives by the end of the month and owners of these lethal weapons must hand them to police by then.
Zombie knives have multi-edged blades, with images, words or markings on them suggesting they are intended to be used for violence.
NSW Police Minister Troy Grant says they have been used in serious crimes in other jurisdictions and are sold online in the state.
"These knives have the potential to cause significant harm to people if used in criminal activity, and there's also a huge risk of accidents by those using them as props or toys," Police Minister Troy Grant said in a statement on Saturday.
"From February 28, it will be an offence to have unauthorised possession of, or to buy or sell one of these knives, without a proper permit."
Anyone caught with a prohibited weapon without a permit faces a maximum penalty of 14 years' jail.
Owners can apply for a permit to have one "but they'll need a good reason for doing so", Mr Grant said.
Other prohibited weapons in NSW include flick, ballistic and star knives, knuckle-dusters and Tasers.
Australian Associated Press