Speaking on US show The Talk, the 30-year-old revealed that she has tested positive for the deadly BRCA1 gene.
Making the announcement shortly after Angelina Jolie revealed she underwent preventive surgery to remove her ovaries and fallopian tubes, Kelly Osbourne explained that she only found out about her diagnosis after mum Sharon made her get tested.
She said: “I actually do have the cancer gene.
“My mum made all of us go and get tested after she found out she had it and got her double mastectomy."
However, just as Angelina has done, Kelly has revealed that she will be undergoing preventive surgery in the future.
She said simply: “I agree with this one hundred percent. I know one day I will eventually have to do it too.
“If I have children I want to be there to bring them up. I want to support them in every way I can.”
The former Fashion Police host went on to praise Angelina for speaking out about her hysterectomy this week, saying: “It’s something I applaud Angelina for because she’s bringing attention to this, and people are now going to go out and get tested for it.”
Speaking about her mother, Kelly added: “I have been the child a child of a cancer survivor and being on that end as well has been really hard to deal with.
“I’m so lucky to have the brave mother I have.”
Sharon Osbourne beat colon cancer in 2002, and, years later, had a double mastectomy after discovering that she had the breast cancer gene.
“As soon as I found out I had the breast cancer gene, I thought: ‘The odds are not in my favor,’ ” she told the U.K.’s Hello! magazine at the time.
“I decided to just take everything off.”