In front of 4,277 fans at Jubilee Stadium, the Matildas raced out of the blocks scoring eight goals inside the opening half-hour, including a remarkable six-goal haul within a nine-minute period at Kogarah Oval in Sydney's south.
Striker Michelle Heyman netted a first-half hat-trick, while there were also doubles for Sam Kerr and Lisa De Vanna in her first match as captain.
Australia was physically and technically superior from the start against a side which it defeated 4-0 in a training match on Tuesday.
Matildas coach Alen Stajcic made five changes to his line-up against a Vietnamese outfit that only narrowly failed to qualify for the upcoming 24-nation World Cup in Canada.
The Matildas lost a little bit of momentum as the match wore on after a downpour late in the first half, and a string of second-half substitutions.
While Australia looked strong throughout it did profit on several occasions from poor handling by Vietnamese goalkeeper Dang Thi Kieu Trinh.
There were just three second-half goals for the passionate crowd to cheer and only a single strike during the final half-hour via the boot of substitute Caitlin Foord.
Katrina Gorry, Laura Alleway and Emily van Egmond were the other scorers on the night.
Stajcic was ecstatic with the result his team achieved as its prepare to depart for a World Cup where it has a real chance to go deep into the tournament.
"The first 25 minutes at the start was amazing, and I haven't seen such a clinical display as that," Stajcic said.
"When we played Vietnam 12 months ago we only won 2-0 and that shows how far we have come.
"There was a lot of good stuff but for us to be a top world class team we need to be more consistent over 90 minutes.
"We seemed to finish everything but I was more pleased with the passages of play that constructed some of the goals and I think that will work against anyone."
The scoreline fell well shy of the Matildas record 21-0 scoreline achieved against American Samoa in 1998.
The Matildas depart for Canada on Saturday where they will face a far greater task having been drawn against world No.1 USA, European powerhouse Sweden and African champion Nigeria.