The 47-year-old actress is currently staying in Melbourne, where Neighbours is filmed, with her Australian cricketer fiancé Shane Warne, after the pair became engaged last year.
Tweeting to her 333,000 followers, Hurley wrote: "My son totally overexcited as he's visiting the Neighbours set today."
Hours later, she followed up with the tweet: "My son in heaven-he got to be an extra in Neighbours today."
In reply, Alan Fletcher, who plays Karl Kennedy on the soap, tweeted: "@ElizabethHurley your son was terrific on the @neighbours set today. He seemed to have a great time. What a charming lad he is."
The Austin Powers star has previously revealed that 10-year-old Damian wants to become an actor, and is "begging her" to find him an agent.