The British author discussed the impact of press attention on her life after she sprung to fame due to her Harry Potter books enjoying worldwide success.
Rowling told the inquiry about several attempts to stop press photographs of her children from being published, including one of her 8-year-old daughter in a swim suit on a beach in Mauritius.
She took that case to the Press Complaints Commission (PCC), which found in her favour, but she said that defamatory articles can "spread like a virus" around the world.
"A child, no matter who their parents are, deserves privacy. They have no choice in who their parents are; they have no choice in how their parents behave," she said at the Leveson Inquiry.
"As far as children are concerned, I think the issue is black and white. I think it would have to be an extraordinary public interest to publish photographs of children, particularly without their consent."
Rowling said that she felt like a "hostage" for a week after the birth of her third child, as it was impossible to leave the house without being photographed.
At one point the Harry Potter author stated, "I can't put an invisibility cloaking device over myself and my house."
She also recalled a separate incident when two journalists from a Scottish tabloid camped outside her home in a car, and when challenged as to why they were there, they replied: "It's a boring day at the office."
"My family and I were literally under surveillance for their amusement..It's incredibly threatening, it feels threatening to have people watching you," said Rowling.
The author further discussed a time when she found a letter from a journalist inside her child's school bag, which had supposedly been placed there by a mother at the school.
"My daughter, this is my eldest daughter, so this would have been in the first burst of publicity surrounding me.. She was in her first year at primary school and I unzipped her schoolbag in the evening, and among the usual letters from school and the debris that a child generates, I found a letter addressed to me and the letter was from a journalist," she said.
"It's my recollection that he said he intended to ask a mother at the school to put this in my daughter's bag. I know no more than that. I can only say that I felt such a sense of invasion that my daughter's bag. It's very difficult to say how angry I felt that my 5-year-old daughter's school was no longer a place of complete security from journalists."
One of the most upsetting incidents she said was when journalists from the Scottish Sun went directly to the headmaster of her daughter's school, with the claim that her daughter had upset other students by claiming that Harry Potter died in the final book in the series.
The journalists claimed that there had been complaints from parents about the situation, but Rowling said that this was completely untrue.
"There was not one word of truth in it. There had been not one complaint," she said.
She said that she was driven out of her first home, which was bought with US advances from her first book, in 1999 as press attention had made it "untenable to live in".
She said because of "doorstepping" by reporters and photos published showing the number of the house and the street name, she had been made a "sitting duck" for anyone who wanted to find her.
However, Rowling said that she does not believe she was a victim of phone hacking by the newspapers as she "barely used a mobile phone in the 1990s".
Rowling said that she was not looking for "special treatment" from the inquiry, rather she just wants newspapers to secure her permission before photos are published.
Lord Justice Leveson Inquiry coverage roundup:
> Sienna Miller 'baffled and intimidated' by press intrusion
> Madeleine McCann parents Kate and Gerry 'violated' by press intrusion
> Phone hacking goes beyond News of the World, says lawyer
> Steve Coogan: Newspaper industry is like the mafia
> Phone hacking made Dowler family think Milly was alive
> Hugh Grant suspects Mail On Sunday of phone hacking