Steenkamp was born in Cape Town and raised in Port Elizabeth. Her parents are Barry Steenkamp, a horse trainer, and his second wife June. She was of Dutch and German ancestry. During her early twenties, she broke her back in a horse riding fall, and had to learn how to walk again. She was a paralegal. She dated rugby union player Francois Hougaard. At the time of her death, Steenkamp was dating Paralympic and Olympic athlete Oscar Pistorius.