The furry feline has been a familiar face on the steps outside Number 10's black door since he moved in, in 2011.
And the "chief mouser" will stay when Theresa May replaces Cameron as UK prime minister.
"It's a civil servant's cat and does not belong to the Camerons - he will be staying," the BBC quoted a government spokesman as saying.
The tabby cat, from London's Battersea Cats and Dogs Home, was brought in to Downing Street in 2011 tasked with tackling a rat problem, after a large black rat was seen scuttling past the No 10's front door in the background of a live TV broadcast.
Larry followed in the paw prints of several Downing Street moggies, known unofficially as Chief Mouser to the Cabinet Office.
He was the first cat to hold the appointment since Humphrey - who was adopted in 1989 after wandering in to No 10 as a stray during Margaret Thatcher's premiership - was retired in 1997.
Cameron said he was "delighted to welcome Larry to his new home" and that he was confident he would be "a great addition to Downing Street and will charm our many visitors".
