Brenda Leyland, from Burton Overy, Leicestershire, was accused of being one of the so-called "trolls" directing abusive messages at the McCanns.
Her body was found days after she was confronted outside her home by a Sky News reporter.
Madeleine McCann disappeared while on holiday In Portugal in 2007.
Mrs Leyland was confronted by the reporter who put to her she had posted messages attacking the family on Twitter via the handle @sweepyface.
She replied: "I'm entitled to do that."
A spokesman for Leicestershire Police said: "Police were called at 13:42 on Saturday 4 October to reports of a body of a woman in a hotel room in Smith Way, Grove Park [in Leicester].
"Officers have attended the scene and a file is being prepared for the coroner. The death is not being treated as suspicious."
Sky issued a statement saying: "We were saddened to hear of the death of Brenda Leyland. It would be inappropriate to speculate or comment further at this time."
A statement released by the Marriott Hotel in Leicester read: "We are very sad to confirm the death of a guest at the Leicester Marriott Hotel and our thoughts go out to the family and friends of the deceased."
On Friday, Madeleine's father, Gerry McCann, told the BBC: "Clearly something needs to be done about the abuse on the internet.Gerry and Kate McCann have been subjected to a sustained hate campaign by internet "trolls"
"I think we probably need more people charged."
He described how he and his wife Kate, who live in Rothley Leicestershire with their nine-year-old twins, do not read posts about them on the internet because it was too "upsetting".
His interview on BBC Radio 4's Today programme followed the news that police were reviewing a dossier of abusive messages about the family on social media.