Police have confirmed a skull found on a construction site in the Perth suburb of Wembley is that of a human.

Demolition workers excavating at the block on Jersey Street made the discovery on Tuesday morning.

One of the demolition contractors says he found the skull in the bucket scoop of his excavator and believed it was human.

Police were alerted by a construction crew who unearthed it while working at the site ( Grant Wynne )

The area has been cordoned off.

Police say they believe the skull, that of an adult male, may have been a medical specimen which had been retained by someone in the profession.

Forensic pathologists are expected to examine the remains further.

The trench where the skull was found is expected to be widened as officers search for further clues.

Detectives are trying to contact the owner of the property who is believed to work in the north of the state.