Roberta Sykes was born in Townsville and grew up in Queensland. Sykes attended St Patrick's College in Townsville, but left school at fourteen and worked at a variety of jobs. As a black woman, she suffered racism and violence. By the late 1960s, she was active in the Queensland black movement, particularly the One People of Australia League. In 1972, she was the first executive secretary of the Aboriginal Tent Embassy in Canberra. She later established the Black Women's Action group and lectured widely while working for government departments such as the New South Wales Health Commission. During the 1980s, Sykes attended Harvard University after raising funds and securing support from the Australian Council of Churches. She received both her Masters and Doctorate in Education from Harvard University.
Sykes returned to Australia and continued to write and lecture in various institutions while contributing to many government reports and discussion papers, including the Royal Commission into Aboriginal Deaths in Custody and reports for the New South Wales Department of Corrective Services. She was also Chairperson of the Promotions Appeal Tribunal at the Australian Broadcasting Corporation. Sykes was a guest lecturer at universities and tertiary institutions throughout Australia, and was in demand as an international speaker.
In addition to writing books about the Aboriginal experience in Australia, Sykes also wrote poetry and biographies. Her most significant work is the three-volume autobiography Snake Dreaming (1997-2000). Although the Snake Cradle volume of the trilogy won awards and high praise, the question of Sykes's Aboriginality continued to be raised in heated discussion. While she appeared to have claimed Aboriginal heritage, the possibility that her father was an African-American serviceman frequently resurfaced in commentary about her achievements.