The Sheffield-born actor, who also played Albert Dingle in Emmerdale, passed away suddenly this morning while on holiday in the South of France.
Comedian Bobby had roles in Heartbeat and Last Of The Summer Wine and most recently starred as Eddie Dawson in Benidorm.
Tributes have already begun flooding in for the actor - including from Benidorm writer Derren Litten.
He said: "Very sad Benidorm news guys. The wonderful Bobby Knutt has passed away suddenly aged 71. Sending our Beni love to his family."
The Benidorm TV show account tweeted: "Benidorm star and Sheffield legend Bobby Knutt passes away aged 71. Good night Knutty, your Benidorm family loves you. X".
Tony Maudsley, who plays Kenneth in the show, said: "Take a bow Grandad Dawson. Your Benidorm family will miss you. RIP Bobby Knutt x".
Actress Stephanie Dooley Day wrote: "So sad to hear the lovely Bobby Knutt has passed away. treasured memories of our panto days! RIP Lovely man".
Jake Canuso said: "Sad to hear of the sudden passing of Bobby Knutt. He will be dearly missed by his @BenidormTVshow family. RIP lovely man."
Bobby was a regular on the pantomime circuit in Sheffield and starred in 14 different shows at the Crucible and Lyceum theatres.
He was married to Donna Hartley - once hailed the "golden girl" of British athletics - before she passed away in June 2013 aged 58.
He was born in Sheffield in 1945 where he started his showbiz career as a singer in group Bob Andrews and the Questors.
Bobby later joined the Whirlwinds in 1963 before forming a comedy duo the year after Pee & Knutt with partner Geoff Morton.
In 1965, Bobby became one of the youngest professional comedians in the country and was known for his performances on Granada Television show The Comedians and The Wheeltappers and Shunters Social Club.
He has since acted in many British favourites - including Stanley in Last of the Summer wine and garage boss Ron Sykes in Coronation Street.
In 1995, Bobby starred in one of his most well-known roles as Albert Dingle in Emmerdale.
He began playing Eddie Dawson - "Grandad" - in ITV show Benidorm in 2016.