Starr, a household name who rose to fame in the 1970s, was found dead at his home in Spain, The Sun said.
A post on Facebook and Twitter pages claiming to belong to Starr appeared to confirm the news.
A post said: ‘This is Freddie's manager Just to confirm Freddie has passed away. R.i.p to our greatest comedian of all time.’
Starr's fellow comic Jim Davidson was among those paying tribute.
He tweeted: ‘Just heard the news. Freddie Starr was the greatest.’
Actor Bobby Davro said on Twitter that Starr was ‘one of our greatest comedy talents’.
He wrote: ‘I've just heard that Freddie Starr has died. He was the funniest man I have ever seen. I'm so sad we have lost one of our greatest comedy talents. RIP Freddie.’
TV presenter Amanda Holden, who is from Bishop's Waltham, said she hopes Starr is ‘remembered with a smile’.
Writing on Twitter, she said: ‘Sad to hear of Freddie Starr passing today. His style may have fallen out of comedy fashion & favour-but it's important to recognise his once huge popularity& fame.’
Britain's Got Talent host Holden, 48, said Starr's parodies were ‘outrageous and edgy’.
Merseyside-born Starr was the lead singer of the Merseybeat group the Midniters during the 1960s and rose to national prominence in the early 1970s after appearing on Opportunity Knocks.
He was known by fans for his eccentric and often unpredictable behaviour.
In 1986, he was famously at the centre of one of the best known newspaper headlines when The Sun splashed with: ‘Freddie Starr ate my hamster.’
The story claimed Starr placed the small creature between two slices of bread and ate it at a friend's home after returning from a performance in Manchester.
But in his 2001 autobiography Unwrapped, Starr said the incident never took place.
During the 1990s, he starred in several TV shows including Freddie Starr (1993-94), The Freddie Starr Show (1996-98) and An Audience with Freddie Starr in 1996.
He took part in the 2011 series of I'm a Celebrity ... Get Me Out Of Here but dropped out due to ill health.
A meal of fermented egg and a camel toe forced comic Starr to leave after he suffered an allergic reaction and had to be taken to hospital.
Medics advised Starr to drop out of the competition in case his illness flared up again.
Police investigated an allegation of historical sexual abuse against Starr in 2012, which he said left him ‘suicidal’.
Starr was told in 2014 he would not be prosecuted after spending 18 months on bail.
He lost a damages claim against his accuser in the High Court in 2015.
In an interview with the Mail on Sunday, he revealed he moved to Spain following the ruling, which left him facing a bill unofficially estimated at about £1 million.
He told the paper: ‘No matter which way I turned there was a f****** revolver pointing at my head so I thought 'I'm not going to tell anyone, I'm just going to get on a plane and go to Spain, the place I love, and this is where I'm going to die'.
‘I didn't even know how high the legal fees were until after I'd left Britain.’
He added he had not moved "to deliberately get out of paying" and had planned to emigrate regardless of the outcome.
According to The Sun, Starr was found dead inside his apartment in the resort of Mijas on the Costa Del Sol.