Born in Shoreham she lived there until the age of eight. Her father, a sound engineer for Pink Floyd, died when she was seven years old. Then with her mother relocated to North Wales, where they lived with Naomi's grandparents, until the age of 14 when she moved to Sydney, Australia. She attended North Sydney Girls' High School in Sydney. Naomi went to several acting schools where she met her long time friend Nicole Kidman
. She made her acting debut in the 1986 Film For Love Alone.