Anthony LaPaglia is engaged to his 28-year-old girlfriend

Australian actor Anthony LaPaglia and Alexandra Henkel are set to wed.

The couple, who have been dating since 2015, were at the YSL Beauty Club Takes Over Melbourne event on Thursday when they confirmed their engagement

Alexandra, 28, wore a huge engagement ring and kissed and caressed her 58-year-old fiancé for the cameras.

The Without A Trace star split with his wife, Gia Carides, after 17 years of marriage in March 2015.

Three months later he announced he was dating Alexandra.

Last year the award-winning actor spoke about his marriage with The Herald Sun.

"People say 'it’s failed'... My attitude is that it didn’t," he explained. "Twenty years is a long time for any relationship and so many positive and great things came out of it — my daughter being one of them.

The pair married in 1998 after starring in film Lucky Break together.

"It’s an emotionally tough thing to go through but it happens and it’s about adjusting to the fact that people change, life changes."

Gia and Anthony, who was previously married to actress Cherie Michan, shares joint custody of his 15-year-old daughter Bridget.

Melbourne-born Alexandra often shares photos of her husband-to-be on her public Instagram account.

The pair were together in Paris recently, and two weeks ago Alexandra shared a selfie of herself wearing her engagement ring, with the caption, "Such a nice lunch with my love ❤️"