Watt produced a strong finish to the event, recording rounds of 64 and 66 over his closing 36 holes to finish five shots ahead of Queenslander Viraat Bhadwar with a further shot back to New South Welshman Brett Drewitt.
Watt began the final day tied with Queenslander James Gibellini who struggled to build momentum after a bogey at the first and a triple bogey at the par 5 11th saw the end of his challenge.
Four birdies and an eagle in his opening nine holes gave Watt a clear and eventually winning advantage.
Pre tournament favourite Cameron Smith added a final round of 68 to finish alone in 4th position.
Watt is currently ranked 16th on the Australian Men's Amateur ranking but will move higher as a result of this event being a national ranking event.
Watt will now head back to Perth where he will tee it up in the West Australian Open at his home course of Royal Perth.
For many of the others in this week's field however they will head to the Southport Golf Club for the Queensland Strokplay Championship beginning on Sunday and the prelude to the Queensland Amateur Championship to be played at Pacific Harbour on Bribie Island beginning on the 25th of October.
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