"Bill lived and breathed film from his earliest years, working tirelessly to create a demand from New Zealand audiences for the highest quality films from around the world," Fitzgerald said.
Film festival director Marten Rabarts said it was a sad day for the film industry in New Zealand and worldwide.
"The film community in New Zealand owes Bill a huge debt of gratitude for the decades of work and passion he committed to develop and champion a world-class festival experience for audiences and filmmakers alike."
Last year, Gosden featured in a Facebook post from Bowel Cancer New Zealand, saying he wished he had been able to get a colonoscopy earlier.
He had told his GP he had irregular bowel habits, but his blood tests were fine, so his doctor did not worry.
"I was very fit, so I think that masked my illness. It's so annoying.
"I would encourage people to definitely get screened if they are worried," Gosden said.
Despite three rounds of chemotherapy and surgery, the cancer metastasised to his lungs.
He told Standing Room Only last year that when his oncologist told him recently that now was the time to go out and do the things he wanted to do, his response was: "I've spent most of my life doing exactly that."
"I think I've been incredibly lucky with what I've done."
Gosden's family and close friends have asked for privacy while they come to terms with their loss.