"My dear remaining fellow Australians, the end of the world is coming," she says, tongue in cheek.
"Whether the final blow comes from flesh-eating zombies, demonic hell-beasts or from the total triumph of K-Pop, if you know one thing about me it is this -- I will always fight for you to the very end."
The prime minister says there is a bright side to armageddon, which she noted had not come as a result of the much-hyped Y2K millennium computer bug in the year 2000 or due to Australia's corporate pollution tax.
"At least this means I won't have to do Q and A again," she said, referring to a weekly current affairs talk show.
"Good luck to you all."
December 21 represents the end of a cycle in the Mayan long count calendar that began in the year 3114 before Christ.
A doomsday industry has boomed in Hollywood around the notion that the calendar's end will bring the fiery end of human civilisation, with the blockbuster "2012" depicting Earth being swallowed by floods, earthquakes and volcanic eruptions.
The Mayan culture enjoyed a golden age between 250 AD and 900 AD in present-day Mexico and Central America, before its steady decline and the arrival of Spanish imperialists in the 16th century.