Neylan (Building Champions team) rode to the finish solo just weeks after clinching silver at the Mars Cycling Australia Road National Championships.
"I've been waiting a long time to win a big race and it's finally happened," Neylan said.
After two years of struggle with injury and misfortune, Neylan has regained her form to again place herself among Australia's best.
"After my result of second at the Nationals, I was really frustrated not to win that race and I really wanted the green and gold jersey so I guess this is the consolation prize," she said.
Recent Santos Tour Down Under victor Valentina Scandolara (Orica-AIS) finished in second place, 46 seconds behind while Tessa Fabry (High5 Dream Team) rounded out the podium, 48 seconds later.
Exactly 67 starters started the 113km Subaru National Road Series event raced around the Geelong region including the Great Ocean Road and Bellarine Peninsula.
Neylan attacked a reduced peloton with eight kilometres remaining to seal the victory with plenty of time to celebrate.
"I just put my head down and went for it," Neylan said. "Experience pays off and I think I stayed quite patient and I really tried to play my cards and my strengths to win the race.
"My legs were feeling pretty good, but at that point, when you know you can win a race you don't listen to your legs at all, you just go.
"I honestly didn't think I was going to stay away, Orica-AIS are really, really strong and they're all classy riders. It was just my day."
Earlier in the race a crash split the peloton in two, with five riders forced to withdraw.
Kendelle Hodges from new High5 Dream Team attacked solo at the 78km mark and led until the 91km stage of the race before the pace of Orica-AIS saw her swallowed up by the peloton.
Valentina Scandolara retains the Subaru National Road Series leader's jersey. The series continues with the Jayco Adelaide Tour on 9 April.