Cunliffe's family placed a death notice in their local newspaper, the Ilkley Gazette, announcing that he died and was buried after a private funeral, theguardian.com reported.
"[John Cunliffe] left his Ilkley home in a deluge of rain, never to return," read the notice.
"Even the skies wept for John, the gifted creator of 'Postman Pat', 'Rosie and Jim' and author of many earlier published collections of poetry and picture storybooks for children."
Cunliffe created the character of Postman Pat Clifton and his black and white cat, Jess, who lived in the fictional village of Greendale after being inspired by his time living in the Lake District.
He wrote the show on an old Triumph typewriter in the back bedroom of a house in Kendal and teamed up with the animator Ivor Wood, who had worked on the 'Magic Roundabout', 'The Herbs', 'The Wombles' and 'Paddington Bear'.
In 1994, Nick Davies wrote that when Cunliffe raised concerns about the direction his creation was going and the volume of promotional merchandise being created, he "protested quietly and was told to face commercial realities".
His other major success was 'Rosie and Jim', a show about a pair of rag dolls "who gently meandered around the British countryside on a canalboat".
It was produced by Ragdoll, the same company that went on to produce Teletubbies.