Aruna, 66, was one of the comatose patients for the longest duration of time and the face of the debate on euthanasia in India.
She was put on ventilator support in the ICU of the KEM hospital at Parel after she suffered from a serious bout of pneumonia last week.
Actor Rishi Kapoor tweeted, "RIP Aruna Shanbaug, nurse, battling for life since 1973, passes away."
"Such a sad ending! R I P #ArunaShanbaug," wrote Neha Dhupia.
"A 42-yr struggle ends as #ArunaShanbaug leaves for a better life in a better world. A chilling story rewritten by KEM's compassion. RIP," he wrote.
Satish Kaushik said, "42 Years... My god... Terrible.. Aruna Shanbaug at last got rid of her miseries and pain... May heaven be the happiest place for her... RIP.