The moggy died last week at the home of a Cabinet Office worker who took him in when he was "evicted" from Downing Street.
Humphrey left Number 10 shortly after the Blairs moved in in 1997 amid reports that Cherie did not like him.
In 1997 official questions were asked in the House of Commons about his disappearance from Downing Street.
Humphrey also went missing while John Major was in Downing Street.
He was presumed to have died then.
But he was returned when staff at a Westminster medical college read his obituary and realised the cat that had walked into their building was Humphrey.[/quote:2c471]
The 10 Downing Street cat Humphrey has died, a spokesman for the prime minister has confirmed.
The black and white feline passed away at the home of a Cabinet Office worker who took him when he "retired".
Humphrey was adopted by Number 10 after wandering into the building as a stray while Margaret Thatcher was PM in 1989.
He moved out six months after Labour's 1997 general election win, with Tony Blair's wife Cherie denying reports her dislike for the animal was to blame.
"I can confirm we have been told that Humphrey sadly died last week some time," a Downing Street spokesman said.
'Chief Mouser'
Official questions were asked in the House of Commons about Humphrey's absence after his departure from Downing Street in 1997.
A Conservative MP demanded proof that the moggy - sometimes given the nickname Chief Mouser to the Cabinet Office - was still alive.
Downing Street said Humphrey had been suffering from a kidney complaint.
The media were later invited to a South London property, where Humphrey was photographed, hostage-style, with copies of the day's newspapers.
He had also gone missing while John Major was in Downing Street.
At the time it was thought he had died.
But he returned after staff at a Westminster medical college read his obituary and realised the cat that had made his way into their building was, in fact, Humphrey.
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