Dolly magazine sparked controversy earlier this month after it chose Kirsty Thatcher as the winner of its national model search.
Thatcher's prize includes a cover-shoot with the magazine and a contract with the high-profile Chadwick Model Agency.
Harris, 21, also started modelling at the age of 13 after making it to the list of finalists in a similar model search competition run by Girlfriend magazine.
She says providing models have supportive management, starting a modelling career at a young age is not a problem.
"I do think it's fine as long as they've got good management and they're considerate of how young the girl is," Harris said.
"When I started modelling I was 13 as well. It worked out well."
Harris has appeared on magazine covers including Vogue and Madison, and is the David Jones young women's fashion ambassador.
"The agency did really well. They nurtured me. I still continued to do school. I finished school," Harris said of her early experience in the industry.
"They understood that I was so young and didn't push me into anything too drastic."