The local arm of the corporate giant best known for Big Macs and Quarter Pounders told the Herald Sun it would not detail the depth of the decline.
But yesterday it pledged a burger fightback, promising cheaper menu items and a greater variety of meals aimed at Australian tastebuds.
"It's no surprise that with consumer confidence low Australians today are looking for much better value for money," McDonald's spokeswoman Skye Oxenham said.
"We are always looking at exciting new menu items as well as bringing back old favourites."
These include putting more lamb on the menu after Australians embraced the recent lamb burger promotion.
. It also includes upping what it called "quintessentially Aussie menu items" in time for Australia Day.
Ms Oxenham said McDonald's had listened to feedback by introducing its Loose Change menu, with items $3 and under, to combat the customer downturn.
The pledge came after the hamburger chain told US investors that global restaurant revenue had fallen for the first time in a decade as greater competition and tough economic times bit into the bottom line.
Sales in the region fell 2.4 per cent, McDonald's said, point- ing to drops in Australia, Japan and China.
The corporation based in Oak Brook, Illinois, released the figures showing worldwide revenue had dropped 1.8 per cent last month. McDonald's hasn't suffered such a drop since March 2003.
The group also revealed revenue fell 2.2 per cent in both the US and Europe.
The chain's global chief executive Don Thompson said the company would make its way through the downturn.
"The McDonald's system remains focused on serving the evolving needs of our more than 69 million customers daily," Mr Thompson said.
McDonald's, which started as a single restaurant in San Bernardino, California, in 1940, now makes about $26 billion in annual revenue.
