His winning self-portrait depicts Bell at work in his chaotic Lambton studio, the shower running to keep him clean in these hazardous coronavirus times, working on a painting of his seven-year-old self waving red beach flags that was based on a real primary school photo of him singing Anchors Away at a school fete.

"I loved looking at it," he said of the old photo, "I had such a carefree attitude."

"I"m still carefree," he said when accepting the prize, "but not as much as what I was when I was seven."

The prize was judged by a panel of three: Newcastle Art Gallery director Lauretta Morton, University of Sydney curator and art history lecturer Stephen Gilchrist and Museums and Galleries of NSW gallery programs manager Rachel Arndt.

Bell was selected from a group of 30 finalists, chosen from 350 entries.

The judges' comments lauded the composition of Bell's winning work, and called it a "whimsical and reflective work, most definitely of the times".

Lauretta Morton, in comments at the announcement of the winner on Friday afternoon, said the judges "certainly had our fair share of arm wrestling" in deciding a winner.

The judges gave an honourable mention to the painting of finalist An Nguyen, Self-Portrait in old tshirt (and scowl).

Bell told the story of his work on this painting in a Weekender feature on artists working during the lockdown that appeared in early July.

"I started this painting around the middle of March - just as 'lockdowns' and 'self-isolation' started to become the new rules across NSW," he said.

"I really did not intend this picture to be about COVID-19 at all. I thought I'd just paint a self-portrait standing in my studio surrounded by all my mess. In retrospect, my portrait sure looks anxious and worried.

"And I was."

Bell spent about six weeks on the painting, a rare self-portrait, and his first ever full-body painting of himself.

"I'm pretty critical," he said of making the work. "I did work it hard. I changed it a lot. At one stage there was just a head and shoulder in the foreground. I love the process of changing and reworking it.

"At the end of the session, I got to the stage where I was happy with it... it seems to say everything I wanted it to say."

Bell, 61, is best known for his art work for JJJ and Mambo early in his career. He is particularly well-known in Newcastle for his caricature paintings of dogs and "Dog Beach" (Horseshoe Beach).

Bell's works have been hung in The Archibald Prize and The Sulman Prize, and he has works in the collections of the Australian National Gallery and Newcastle Art Gallery as well as many private collections.

The Kilgour Prize exhibition will be open to the public from Saturday at Newcastle Art Gallery.

Bell's toughest critic is his wife, Claire Martin, who is also an artist. She thought it was ok," he said in an interview with the Newcastle Herald. "She was very complimentary on this painting, she made a few suggestions here and there."

The 2020 Kilgour Prize finalists also include An Sheng, Andrew Bennett, Anh Nguyen, Ben Ryan, Brittany Jones, Bronni Krieger, Corinna Howell, Craig Handley, Dagmar Cyrulla, Daniel Butterworth, Elizabeth Austin, Erik Krebs-Schade, Esther Erlich, Greg Creek, Jacqueline Hennessy, Jordan Richardson, Joshua McPherson, Kenneth Lambert, Kerry McInnis, Kylie Melinda Smith, Lileana Colarelli, Lori Pensini, Lynn Savery, Melissa Ritchie, Oliver Shepherd, Peter Gardiner, Tony Costa, Tracy Dods and Wendy Sharpe.