Playing in the cooler morning conditions at McLeod Country Golf Club, Hillier made a solid start with pars at the first three holes before a bogey at the par-four fourth hole saw her slip over par.
A birdie at the par-three sixth hole got Hillier back to all square, and another at the par-five ninth hole took her to the turn at one-under.
The 28-year-old made solid pars at the 10th, 11th and 12th holes before playing her last five holes in four-under to secure the victory.
Hillier was clearly delighted with finally claiming her first ALPG title, especially after five second-place finishes and a host of top-10 finishes in recent years.
The win also takes Hillier to the top of the 2019 ALPG ClubCar Series points ladder, which will be decided following the final event on the 2019 ALPG Tour, the Findex Yamba ALPG Pro-am, which will be held on Friday.
New South Welshwoman Paige Stubbs finished in a tie for second place with Breanna Gill after both players shot three-under par rounds of 71, and Stubbs dashed quickly to Brisbane airport to fly to China for this week's Hengqin Phoenix Tree Building Orient Golf Challenge on the China LPGA Tour.
In a tie for fourth place at two-under par were Kiwi Chantelle Cassidy, QLD native Katelyn Must and the NSW duo of Rebecca Artis and Celina Yuan, while defending champion, Englishwoman Felicity Johnson finished a shot further back at one-under.
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