A closing round of two-under-par 70 was sufficient to earn the Swede her convincing win, with second place shared by her compatriot Mikaela Parmlid and veteran English player Laura Davies. Both finished with rounds of 68.
Hedwall had been sidelined by a hip problem but it proved to be no impediment at the course in Wiener Neustadt. The 23-year-old bogeyed the long opening hole in her final round but five birdies offset two further dropped shots, and Hedwall was never seriously challenged over the closing holes.
"I'm very happy and especially coming back from injury," she said. "This is more than I could have hoped for. I definitely wasn't expecting to win and I just wanted to make the cut when I came here but I found my game and played really well."
Tour rookie Alison Whitaker had been placed second overnight but the Australian fell away to a share of fourth place, with an eagle at the par-five 18th repairing much of the damage from earlier in her round as she signed for a 73.