Harris, 67, entertained generations of children with his sidekick Orville, a bright green duck who wore a nappy and spoke in a high-pitched voice.
His other popular puppet was Cuddles the monkey whose catchphrase was ‘I Hate That Duck!’.
At the height of his fame, he was a regular on Saturday night television and put on private performances at birthday parties for Prince William and his brother Harry.
His 1982 single with Orville, I Wish I Could Fly, was a top five hit and sold more than 400,000 copies.
Harris, who married four times and had three children, was first diagnosed with cancer in 2013 and became ill again in January.
He died in hospital in Blackpool on April 28.
Comedian Jimmy Cricket and former Coronation Street star Ken Morley were among those at a memorial service at Sacred Heart RC Church in Blackpool.