"Cast and crew from Home And Away are saddened to learn of the passing of former castmate, Ben Unwin," a spokeswoman said.
"Ben's work in the role of Jesse McGregor is remembered with much affection.
"Ben's family and friends are in our thoughts and prayers."
Long-running cast members Lynne McGranger and Ada Nicodemou are both "deeply saddened" by Unwin's death and "their thoughts are with Ben's family", a spokeswoman for the actresses said.
McGranger, who plays Irene Roberts on the soap, described Unwin's death as a "terrible tragedy".
"Sending my deepest condolences to his family and friends," McGranger told The Daily Telegraph.
Nicodemou, whose character Leah Patterson-Baker had a relationship with Unwin's character, told nine.com.au: "I just woke up to the tragic news of Ben's passing, my heart goes out to his family."
Kimberley Cooper, who played Gypsy Smith on Home and Away alongside Unwin, told news.com.au she was "just so sad" to learn of his death.
"He was a gift to come to work with everyday and to be on the receiving end of his friendship was to know unwavering support, loyalty and love," she said.
Cooper led the tributes to her former co-star on social media, posting a photo of them on the cover of TV Week.
In the caption Cooper wrote: "My first TV week cover was with you. We had years of laughter, be it giggles on set trying to get through scenes as lovers or doubled over belly laughs at the pubs after work.
"I will be sad for now, but I promise to tell stories of great joy about our times together. You forever hold a special place in my heart. Love you Onion."
Unwin was nominated for Most Popular New Talent at the 1997 Logie Awards (which was won by Tasma Walton from Blue Heelers), and in 1999, received nominations for Best Actor and Sexiest Male from the Inside Soap Awards.
After leaving Home and Away Unwin went to work in the music world, directing videos for Boy George and Culture Club that included singles I Just Wanna Be Loved and Your Kisses Are Charity.
Unwin later turned his back on showbusiness and completed a law degree. According to a 2016 article in Woman's Day, Unwin was working as a senior solicitor in Newcastle.
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