Rhyll McMaster was born in Brisbane and has worked as a secretary, nurse and a sheep farmer; she also worked in the editorial office of Australian Literary Studies at the time when it was produced in the English Department of the University of Tasmania. In 1965 McMaster published her first poems in the Bulletin. Her poetry has since appeared regularly in many Australian publications. McMaster published her first collection, The Brineshrimp, in 1972, winning the Harri Jones Memorial Award. She has also won the Grace Leven Prize twice. McMaster is widely admired for the fine detail of her descriptive poetry. Attracting equal attention are her explorations of family life and her persistent questions about life itself.
In addition to her poetry McMaster has reviewed fiction for the Sydney Morning Herald and written short stories. She was, for a short time, poetry editor for the Canberra Times.