Ballas said that George Andrew Rich, known as Andy, had died suddenly and posted some photos of fond family memories, along with an emotional tribute to him where she wrote about "so many things left unsaid".
She wrote: "With sadness and a heavy heart my father George Andrew Rich fondly known as Andy, has passed away suddenly.
"My heart goes out to his wife Liz the love of his life who was with him for over 40 years and to all who knew him.
"It’s hard to find the right words at this moment, my father lost two sons in his lifetime and I hope you can all find each other in the after life.
"So many things left unsaid, RIP Dad you will be missed but not forgotten."
The dance expert's father was just a couple of months away from his 84th birthday.
Many of Ballas's Strictly co-stars and former contestants commented on her Instagram post to express their condolences.
Claudia Winkleman wrote: "I'm so sorry. Sending you so much love xxx"
Former winner Ore Oduba added: "I’m so sorry Shirley. Sending lots of love to you and your family."
Ex contestant Ruth Langsford wrote: "I’m so sorry Shirley. Condolences to you and the family and sending you the hugest hug."
Tess Daly, Neil Jones and Ashley Roberts also posted their well wishes.
Speaking to BBC Merseyside, she said: “I’m just getting over five weeks of the coronavirus and I've been on my own and Charlie (her dog) has sat at my feet, snuggled and cuddled and just looked at me.
“I had the passing of my father in the last few days and it’s almost like he knows.
Rich left the family when Ballas was just two years old, and she and her brother David grew up with mum Audrey.
She lost David to suicide and has spoken about how she reconnected to their father after his death.
Ballas had told the Radio Times: "My dad wasn't part of my life until David died, when we grew closer. Now I love him to bits."
Her mother Audrey is currently being treated for cancer.
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