Johnny first shot to fame as a finalist on the third season of The X Factor Australia in 2011, where he then released a string of hit singles including On Top, and Take it Home.
He then competed on (and won) Dancing with the Stars in 2012, before kickstarting his acting career on beloved Channel Seven soap drama Home and Away in the character Chris Harrington - a role which he portrayed for three years.
In 2017, the fan-favourite entertainer revealed that he had been diagnosed with brain cancer, and had undergone surgery to remove the tumour.
Two years later, Johnny was thrilled to announce his cancer was in remission, describing the day he was given the happy news by doctors as the "greatest" of his life.
Sadly, in November 2020, the cancer had returned, and by August 2022, Johnny confirmed that it was now terminal in an emotional interview with Carrie Bickmore on The Project.
"Looking up my diagnosis and my tumour, the average life expectancy was three years. And for me it's been five years," Johnny shared at the time.
"I'm already winning. My goal now is to try and help as many people as I can and also live a happy life."
That same month, the inspirational Aussie released his autobiography, titled No Finish Line, an ode to his ongoing fight, and will to live.
"I understand that the cancer is terminal, but I'm going to do everything I can and I am currently doing everything I can to kick its a**," he said.
That same year, Johnny returned to the Dancing with the Stars stage for a guest appearance, much to the delight of his fans across the country.
7 News brought back their special edition of Spotlight in November 2023, where they followed Johnny around for six months in early 2021.
Tahnee revealed the moment they discovered he had brain cancer, after she took him to the hospital when he struggled to string sentences together.
“At this time, he still had these excruciating headaches, so I was like, ‘I think we should head in and get checked out,'" she added.
Ruffo explained that the hospital discovered a 7cm tumour, in: "my right frontal lobe, which is more or less the size of my fist, and they had to operate immediately."
“I think had his illness not got in the way, he might’ve gone on to do even bigger and better things,” Lynne confessed.
Friends, family, and fans flocked to social media to pay tribute to the beloved entertainer, sharing their messages of condolences and heartbreak.
One year on since Carrie interviewed Johnny on his remission, she was raising money for Carriesbeanies4braincancer in his honour.
"I wasn’t going to ask for money because I know times are tough right now. But Henry and Johnny are a reminder to just ask… Ask…Have you got a fiver," she pleaded on Instagram.
You can donate money that will go towards research into brain cancer, here.
"Oh, darling boy. Sending love to all who knew and loved you. And there are so many," wrote The Morning Show host Kylie Gillies.
"Shattered, An absolute beacon of positivity. Johnny walked into any room and put a smile on everybody's face. Gonna miss ya brother, watch over us," penned radio presenter Fitzy.
"A star has moved to the next world. Go well Johnny," shared comedian Dave Hughes.
"So devastatingly sad. My heart is absolutely broken. Life just isn’t fair. @johnny_ruffo you will continue to be an inspiration to all of us. I’m sending all my love to Johnny’s family, dear friends & beautiful Tahnee," Home and Away actress Sarah Roberts wrote.
Her co-star Georgie Parker sharing a tribute of her own: "Sending love to Johnnys family, friends, and loved ones. He was truly one in a million, funny, bright, and such a hard worker. It's ridiculously cruel that he's no longer here. Rest up now Johnny."
"Oh my. What an incredible human. Sending so much love," singer Natalie Bassingthwaighte also commented.
"Jules Sebastian added that Johnny was a "beautiful soul" who "Brought joy wherever he went."
"Such heartbreaking news to hear. What a beautiful soul who showed so much strength all the way to the end. So much love to his family, partner, and friends. Rest easy now sweet man," said Angie Kent.
"Brave, courageous, strong, resilient, and a fighter til the end, you will be missed by all. Rest easy Johnny 🕊 Love, thoughts, and condolences to his partner, family, and friends," Casey Donovan commented.
Sunrise weatherman Sam Mac also shared in his disbelief: "This doesn't feel real. What a champion you were on and off the stage. Thanks for all the laughs Johnny! You did it all in your 35 years and the integrity and positivity you showed right through to the end was true strength. Go well, mate."
"The cheekiest chap," penned Dannii Minogue, "His voice, smile and dancing feet will be missed by so many. Thinking of his family in this heartbreaking time."
Georgie Parker also commented, "Sending love to Johnny's family, friends and loved ones. He was truly one in a million, funny, bright and such a hard worker. It's ridiculously cruel that he's no longer here. Rest up now Johnny."
Home and Away actress Ada Nicodemou wrote, "Our beautiful friend Johnny, a true Aussie larrikin with a heart of gold. You fought a good fight right to the end, may you rest in peace my friend .💔🙏🏼"
"My heart goes out to Tahnee, just the most courageous, strongest woman I know and to his family. Johnny I’ll always remember the laughs and the shared love of Michael Jackson music. 💔🙏🏼🕺🏻"
His H&A co-star Lynne also shared an emotional tribute to Johhny: "He was our friend and we loved him. But more than that he was a beloved son to Jill, a soulmate to his darling Tahnee, a brother to Michael, a cousin, and a precious grandson to his dearest Nonna."
"He fought like a warrior and was brave and cheeky to the end. Talented, funny, loyal and naughty - we love you, my friend. Fly high free from pain. You are missed."
"You've left this world better than you found it," she said.
"His courage in the face of a terminal brain cancer diagnosis inspired us all. And it was the love for his family that kept his light burning bright."