The 161st-ranked visitors struggled to break through a disciplined Socceroos defence and were visibly flagging by half-time, with a dogged showing by keeper Kiran Chemjong avoiding a bigger blowout.
"We created a lot of chances, but we got a bit more ruthless when it counts," said Australia coach Graham Arnold after his side's biggest home win in three years. "Overall, I'm very happy."
Melbourne City's Maclaren opened scoring in the sixth minute when Chemjong lost his grip on a drive from the top of the box.
He doubled the lead in the 18th with a header off Rhyan Grant.
International debutant Harry Souttar followed five minutes later with his own nod into goal, but a potential fourth by Mathew Leckie seconds before the break was controversially flagged offside.
By then the Aussies had made 16 shots on goal against a solitary attempt by the visitors -- a 44th minute Hail Mary from Abhishek Rijal from near the half-way line.
The visitors rallied in the second half but notched an own goal after failing to deflect Souttar in minute 59.
Late substitutes Ajdin Hrustic and Awer Mabil kept up the pressure but could not capitalise on their attempts before Maclaren made his third in the closing moments.
"(It's) my proudest moment in a football jersey," he told Fox Sports after the match, while conceding that his side squandered a few easy opportunities through the match.
"End of the day we scored five... but looking back we could've scored more," he said.