Taken from his family's banana farm in South Sudan at the age of six and conscripted into the army, Mr Adut witnessed child soldiers like him holding guns to their heads in despair.

The 33-year-old refugee's story is now well-known, thanks in large part to a Western Sydney University advertisement that has been viewed almost 2.5 million times.

It is about to be even better known. On Monday night Mr Adut was named NSW Australian of the Year for 2017 and is in the running to take out the national title on January 25.

The child soldier-turned-Sydney criminal lawyer beat to the coveted title Indigenous broadcaster and reconciliation champion Stan Grant, burns survivor and ironwoman Turia Pitt and biomedical engineer Jordan Nguyen.

In a powerful Australia Day address this year, Mr Adut spoke of the pain of being displaced as a child and the yearning for belonging.

"I was denied the right to become an initiated member of my tribe," he said. "The mark of 'inclusiveness' was denied to me.

"I had to wait until I became an Australian citizen to know that I belonged."

NSW Premier Mike Baird, who made the announcement at the Museum of Contemporary Art, said Mr Adut "represents the very best of what makes our country great, and has channelled his success into helping hundreds of people in the state's Sudanese community navigate their way through the Australian legal system".

An emotional Mr Adut joked: "I want to cry but I just have to man up."

He said a person was not an Australian because they were born in Australia but because Australia was born in them.

What a person did for their country was what made it meaningful, he said.

"I am an Australian for the rest of my life," Mr Deng said.

He added that he did not think a 33-year-old deserved the award.

"What am I going to do with it?" he said.

"However, I understand how important it is."

Mr Baird also named "celebrity doctor" John Knight, 89, who founded the Medi-Aid Centre Foundation in 1973 with his late wife Noreen to provide accommodation for the frail and elderly, as NSW Senior Australian of the Year.

Reconciliation champion Arthur Alla, 27, was named Young Australian of the Year for his work setting up Red Earth, which allows Indigenous Australians living in remote areas to host young people from the city to immerse them in Indigenous culture.

The NSW Local Hero is Josephine Peter, 83, who was honoured for her tireless volunteer work in Broken Hill over 70 years, including knitting hundreds of pairs of socks for Australian troops, working as a telephone counsellor and supporting the Smith Family.

Mr Adut, who survived being shot at the age of 12, was settled in western Sydney in 1998 after being rescued by the United Nations.

He taught himself to read while working the night shift at a Blacktown petrol station and later graduated with a law degree from WSU. He is now studying for his second master of laws, this time in criminal prosecution, at Wollongong University.

A co-founder of AC Law Group, a law firm with offices in Sydney, Redfern and Blacktown, Mr Adut helps troubled youths in western Sydney through pro bono cases.

He was awarded the NSW Law Society president's medal on October 27 in recognition of his contribution to law and justice in the community.

Mr Adut has also turned the tragedy of his brother's death in 2014 into a legacy, establishing the John Mac foundation to provide higher education scholarships to students from refugee backgrounds.

John Mac Acuek, 42, was killed trying to evacuate civilians caught up in the fighting in South Sudan.

Mr Baird, whose father Bruce was famously outspoken in the Howard government over its asylum seeker policies, has described Mr Adut as "living proof of what people can achieve when they are given the opportunity and we as a nation share our luck".

"My genuine and honest fear is what will happen to Australia if we shut our doors to people such as Deng, whether it be out of fear or ignorance," Mr Baird said in his Australia Day address this year.

"We have a choice to continue on the path that brought this nation to where and who we are today, or we can let fear blind us and hate infect us."