The Nursing and Midwifery Council (NMC) said yesterday that Patricia Dowdy "failed to provide the standards of good, professional care that we expect and Professor Hawking deserved".
The 61-year-old, who worked for the scientist for 15 years, was handed an interim suspension in March 2016.
She faced multiple misconduct charges in relation to the care she provided to the scientist, who died in March last year at the age of 76.
The NMC said the charges included financial misconduct, dishonesty, not providing appropriate care, failing to cooperate with the nursing watchdog and not having the correct qualifications.
A hearing into her professional conduct, which began in February, was held behind closed doors.
Matthew McClelland, director of fitness to practise at the NMC, said: "The panel has found Mrs Dowdy failed to provide the standards of good, professional care that we expect and Professor Hawking deserved.
"As a result, Mrs Dowdy will no longer be able to practice as a nurse.
"As the public rightly expects, in serious cases such as this - where a nurse has failed in their duty of care and has not been able to evidence to the panel that they have learned from their mistakes and be fit to practise - we will take action.
"We have remained in close contact with the Hawking family throughout this case and I am grateful to them - as they approach the anniversary of Professor Hawking's death - and others for sharing their concerns with us.
"My thoughts are with the family at this difficult time."
Andrea Sutcliffe, NMC chief executive, said on Monday that hearings are sometimes held in private to keep information confidential.
"That is the basis upon which this particular hearing was conducted in private and I stand by that decision," she wrote in a blog post.
"No public interest is served by exposing the details of the health or care of an individual whose anonymity may not be guaranteed in an open hearing."
A spokesman for the family said: "The Hawking family are relieved this traumatic ordeal has now concluded and that as a result of the verdict, others will not have to go through what they suffered from this individual.
"They want to thank the NMC for their thorough investigation."
Professor Hawking, one of the most renowned scientists in his field, was diagnosed with motor neurone disease in 1964 at the age of 22 and given just a few years to live.
The father-of-three was later confined to a wheelchair and relied upon a computer to communicate, but continued to travel the world to present lectures and further scientific knowledge.