The world number 16 American has been the form player of recent months, and has now scored two wins and two other top three finishes in her last five events.
In carding a 17-under-par 271, holding off South Korean challenger Ko Jin-young, Korda joined her father, sister and brother in being crowned an Open champion on Australian soil.
Dad Petr got the ball rolling by winning the Australian Open tennis Grand Slam in 1998, beating Marcelo Rios, and celebrated with his trademark scissor kick.
Her sister Jessica then won the Australian Open golf in 2012, duplicating her father's celebration, as did brother Sebastian when he took out the Australian Open tennis boys' title last year.
Not to be outdone, Nelly also nailed the "Korda Kick" after her final round 67.
Just minutes after tapping in a par putt at the 18th hole, she was handed a phone and her elder sister was looking at her through Facetime.
Korda put it in context: "I'm finally a part of the club.
"She was pretty much screaming congratulations, she was so happy for me. I mean this win was really special for my family," she added.
"I think there's something in the air here, we love coming Down Under.
"I just got off the phone with my Dad and he said 'well, congratulations, you're part of the Korda Slam now'."
Korda was the overnight leader and held her nerve despite a bogey on the 15th to beat Ko by two and Taiwan's Hsu Wei-ling by five.
Thailand's world number one Ariya Jutanugarn finished 15 adrift.
Korda headed to Adelaide's Grange Golf Club on the back of her first LPGA victory at the Taiwan Championship last October, before a second place finish at the Tour Championship in Florida.
She started her 2019 campaign in a similar vein, finishing third at the Tournament of Champions last month, also in Florida.