Western Australia's Department of Corrective Services is investigating the stabbing of a murder suspect in a Perth jail.

It is understood Cameron Mansell, who is in Hakea Prison awaiting trial over the murder of his business partner Craig Puddy, was stabbed by a 27-year-old newcomer to the jail.

Stephen Michael Freeman, 27, was only sentenced on Monday for the stabbing murder of a 21-year-old man in suburban Tuart Hill.

The Supreme Court was told Freeman listened to an iPod while he repeatedly stabbed his victim in the neck and chest.

The extent of Mansell's injuries is not known.