Lynne Maguire, 19, was raising money for the World Cancer Research Fund when she completed the jump last Saturday.
She said, "My grandparents died from cancer in July within three weeks of each other. It was so very sad for the whole family, as they had just celebrated their 50th wedding anniversary.
"At the beginning of July we were holding a funeral for my grandmother Anne who had been suffering from cancer of the bladder.
"My grandfather, Edward, had been so busy caring for her he hadn't realised how ill he was as well. He thought he just had back problems.
"Then, when my grandmother died, he went to the doctors to sort out his back and discovered he had cancer in his liver and kidneys.
"This is why I wanted to do a sponsored skydive for WCRF. I don't want any other family to go through what we have been through.
"It's the first time I have ever done anything like this and I was very nervous but also excited."
Lynne's family and her boyfriend, Dan, 22, supported her on the day.
Natalie Tarrant, events manager at WCRF, said, "We are so grateful to Lynne for taking on the skydive for us.
"The money Lynne raises will go towards our research and education programmes into the link between lifestyle and cancer."
To sponsor Lynne, visit www.wcrf-uk.org/sponsor