The sad news was first revealed by Denis' cousin Neville Quist who took to Facebook to share a heartfelt tribute.
"Denis Sheridan my legendary cousin has exited the stage for the very last time," Neville wrote.
"The King of Swing and former Lord Mayor of Unley who opened for Frank Sinatra at Sanctuary Cove has sadly passed away yesterday (Monday) surrounded by his beautiful loving family."
Following the heartbreaking news Hugh shared a touching tribute to his late father with a beautiful video montage via Instagram.
"It's taken me moment to pay tribute for my late (often late but never for a gig) father Denis Anthony Dominic (Dad) Ignatius Sheridan. So if you're a friend or follower, a stranger who's scrolling... take a moment in your break to watch a song/poem for my dad," he began.
"The recording is one we did at the legendary "Sing Sing" studios in Melbourne. My sincere apologies to the many I haven't responded to yet, my best mate and father appreciate your love immensely.
"Thank you to darling kurt_roberts for your help with video :) RIP Dearest Denis, you were always a star and now you always will be 🌟 🌈."
WATCH BELOW: Hugh Sheridan pays tribute to late father with heartfelt post
Hugh opened up about his father this year, explaining that he suffered from a terminal Illness which was why he decided to jump into the deep end with his partner Kurt Roberts and propose.
Indeed, at the Adelaide Fringe Festival in March, Hugh proposed to Kurt on the first night of his breathtaking dance performance.
The pair later celebrated their relationship in a beautiful soiree.
"Remembering a couple of weeks ago when @majesticmsuites in Adelaide threw an unforgettable little soirée in their beautiful court yard for Kurt and I," Hugh wrote in the aftermath of the celebrations.
This story originally appeared on our sister site, Now To Love.