Science fiction publication Locus Magazine has confirmed the 74-year-old died peacefully in hospice care in Tucson. She first suffered a stroke in February and was admitted to care in April after a further series of strokes.
The lesbian writer first came to prominence in the late 60s in a science fiction world largely dominated by men. She is lauded as being one of the most outspoken authors to challenge male dominance in the field, and is generally regarded as one of the leading feminist science fiction scholars and writers.
Russ was best know for The Female Man, which was published in 1975. She suffered from health problems including back pain and chronic fatigue syndrome, which reduced her writing output.