The six finalists each performed three pieces - one accompanied by pianist Terence Dennis and two arias performing alongside the New Zealand Symphony Orchestra, conducted by Emmanuel Joel-Hornak.
British soprano and vocal teacher Kathryn Harries was the contest's Grand Final international judge and said all six finalists had international singing careers ahead of them.
"In coming years, I look forward to seeing their names on programmes all over the world."
Ms Harries said Moore's performance stood out for the combination of vocal technique, musicianship, expressiveness and the x-factor.
"All six finalists were very close and it did come down to the performance on the night."
Moore won the title singing Rachmaninoff's Spring Waters accompanied by Terence Dennis and two arias performed with the New Zealand Symphony Orchestra; Mozart's Come scoglio from Cosi Fan Tutte and Massenet's Pleurez, pleurez mes yeux from Le Cid.
For the win, she received a $15,000 study scholarship, cash prize of $10,000, plus a return economy international airfare.
Runner-up, Wilson, received a $10,000 study scholarship and a cash prize of $8000. The cash prize for the runner-up of the Lexus Song Quest was supported by the Dame Malvina Major Foundation.
Third prize-winner, Thurston, received a $5000 study scholarship and a cash prize of $5000.
Finalists each received cash prizes of $3500.
