NSW Ambulance received reports just before 10am that a worker had suffered a laceration to his leg while working on the roof of a construction site near Lake and Main roads at Glendale.

Emergency services arrived at the scene where the man reportedly could not get down as a result of his injury.

SafeWork inspectors have commenced an investigation into the incident and have issued a number of notices to the employer, a spokesperson told the Newcastle Herald.

The worker was injured while moving materials onto the roof of a worksite, the spokesperson said. He suffered a "deep laceration to his leg" and was rushed to hospital.

Investigations are continuing.