Pironkova blasted her way past German fifth seed Angelique Kerber 6-4 6-4 to secure her long-awaited first title after eight years and more than 200 tournaments as a professional player.
The world No.107 dedicated her breakthrough triumph to her late grandfather, Nikola.
"Where do I start? Mum, dad, I have a trophy," the 27-year-old said in an emotional victory speech.
"I'd like to dedicate my first title to a very special person, who is not among any more, my grandfather Nikola. I know you're here tonight. I love you."
Pironkova, a one-time Wimbledon semi-finalist who has been ranked as high as 31st in the world, will now face little-known Spaniard Silvia Solar-Espinosa in her first round of the Australian Open next week.
But the Bulgarian, who has now emerged as a player to avoid at Melbourne Park, will likely have to get past Samantha Stosur in second round if she's to stay on course for a possible fourth-round date with world No.1 Serena Williams.
Kerber was Pironkova's third top-10 victim of the week, with the Bulgarian having also accounted for French Open runner-up Sara Errani and former Wimbledon champion Petra Kvitova on her way to the title.
Pironkova, who will surge up the rankings to crack the top 60 after becoming the fist qualifier in three years to win a WTA tour event, prefers to play on grass, having reached the semi-finals, quarter-finals and fourth round at the All England Club.
But she looms as a dangerous floater in Melbourne after racking up eight straight wins on the Sydney hard courts this week.
Kerber had cruised to the final without dropping a set but was came up against tough opponent in Pironkova.
The Bulgarian, who appeared troubled by a left groin injury and, like Kerber, was sporting strapping on her right thigh, gave away her first set point but wrapped up the opening set on her second.
Pironkova spurned several chances to keep her momentum going and get the early break in the second set, with the marathon second game featuring 11 deuces before Kerber, who wasn't going down without a fight, finally held serve.
At 4-4, Pironkova played an almost flawless service game, blasting a cross-court volley to take the lead.
Kerber stepped up to serve and keep herself in the match but, at 15-40 down, the steely Pironkova got her first championship point and only needed the one to clinch the match.